Car! We've had Renaults for years, but last time we went for a BMW and the difference is night and day. My wife had to do lots of stretching exercises just to go and buy bread. In the BMW she can happily drive 5-6 hours with no (extra) discomfort.
I totally get why you might not but for me, quality underwear has been a great purchase. They last longer, breath better, stay put, and synthetic ones are washable in a sink in a pinch when traveling(I mean they all are but these dry really quick)
Office chairs are important, but people tend to overlook the rest of their office ergonomics. If you work at a computer you should spend money on an adjustable keyboard tray and monitor arms. Then buy a good ergonomic keyboard and vertical mouse or trackball to go with them. My back and wrists used to get sore by the end of the day. That hasn't happened since I upgraded my gear.
Coffee beans for sure (gotta love freshly roasted specialty beans!), but also vegetables (organic & local are the best). Oh, and also headphones, for sure.
To me these are all totally worth it because the jump in quality is very noticeable. After a certain price point, though, the law of diminishing returns kicks in hard
I came across a saying "Buy nice or buy twice" and that resonated with me. Another variation I have seen is "Buy once, cry once".
Getting cheap trash that will fall apart in a few months that you will have to eventually re-buy isn't going to help, but that doesn't mean you buy gold-plated or diamond-encrusted items. Spending a little bit more for most items usually gets you something that will work better, last longer, or both. Good quality stuff is usually backed with good warranties too.
I spend my time researching to see what product is the best for me, look for deals online, or even buy used if I have to.
As some have mentioned, OEM car parts, particularly anything electrical. It’s just not worth the money saved on cheaper aftermarket parts that may not work even though they are new. It often leads to unnecessary troubleshooting and sometimes even more parts, only to land right back where you started.
Stuff from locally-owned stores. Tools, supplies, car parts, food... if the markup isn't egregious, I'll always try and get from them before a big box or online. Not only does it help the owners, but they're frequently knowledgeable and can sometimes work stuff out for you.
Honey and Olive Oil. Not always, because the good (i.e. real) stuff can get pretty expensive, but for uses where it's centre stage, the difference is massive.
Headphones.
I first used some cheap ones and then switched to Bose. The difference was significant. Never again cheap headphones..
Also my ears thank me because I can listen to music with lower volume than with the cheap ones.
YouTube premium. I'm too old to hassle with extensions, and I really don't like ads. And I like to support my content creators without going to twitch or clicking on any links in their descriptions.
It's pretty niche and it's not "a little more"..more like double...but as an equestrian I will always go big name for a saddle. Spent too many years compromising and there is SUCH a significant difference that I will never go sub $2000 for a new saddle.
Generally speaking, electronics are the one thing that almost always follows the "you get what you pay for" rule. To a point, though. Headphones, for example, are better the more expensive they get. Up until they're about $200, that is. Anything higher than that is just wasted money.
I'll go for $20 sunglasses because I lose them constantly and Costco cheap for a lot of stuff because they have enough customer service (that I won't exercise) to think it's not bottom of the barrel, but there's just a bunch of stuff where the money you save by buying the cheap version disappears when you have to replace it.
Specifically in terms of spending more than most would, my ereader is up there. It was like $700 for the discounted "refurb/open box/whatever" version, but it's 13.3" with great sharpness and Android so I can get content from a broader variety of services without jumping through hoops. It wouldn't be worth it for most people, but I've read enough books through it in the time that I owned it that I don't regret it at all (and wish I spent more for the newer version that has a light).
So I'm a writer, and I've paid like $50+ for a software called Scrivener. I like Google Docs for the odd write up here and there. But when I'm writing something fiction, non-fiction, fanfiction, Google Docs slows TF down. That and Scrivener has different pages for each chapter, and character pages. I love it.
It's super expensive but I've been able to move the key from my laptop to my PC and I have it on another PC, I even bought the iPad version for $30aud. Like it's expensive but you only pay once and if you enter Nanowrimo (National Novel Writing Month -- you write 50k words in a month) you get a 10% discount and if you win you get 50% off. There's people who have won before who give out their win code.
I'm bias due to my profession, and regularly get attacked for this point on the Internet by people who think they know better, but glasses.
My eyes aren't even bad, but when I wear them, holy shit is there a difference between the high tech new stuff and basic lenses.
Anyone that tells you online glasses are just as good has never had a 600$ pair from a real (not chain) optical. Anyone who says they have got ripped off by Pearl vision or LensCrafters.
Pet food. I have done a lot of research into the pet industry in general and there are a lot of things being sold for pets that are literally unsafe for them. Like cages that are too small, treats that aren't safe for them, chew toys full of toxic shit they shouldn't invest, food that is the equivalent of McDonald's every day, etc
Don't get me wrong, there's good quality pet food you can get fairly cheap and bad quality pet food you can get that is very expensive. It comes down to research. But if you're just grabbing whatever is cheapest is most likely setting you up for potential health issues down the line.
This is speaking as someone who has experienced this with both cats and rabbits. The cheapest food for rabbits is usually full of alfalfa and whatever else weird ass colorful shit they threw in there that is not healthy for adult rabbits. And cat food is usually too high in carbs, too high in salt, or both. Diabetes and kidney failure in cats fucking sucks, it's not worth it.
I looked a very long time after my backpack of 10 years broke and found one with a lifelong warranty that feels like I‘ll have it for at least 20 years.
Motor oil and oil filter. I only use mobil 1 and their extended life filter.
Edit to add: I don't know of any shop that will use that oil/filter so I do my own oil changes and even with the "expensive" oil (5 qt. jug from walmart is about $29 and free delivery) it is much cheaper to diy this than have it done.
ETA: Just looked up that price and I was off by $2 so updated it to $29.
Fudge stripes! Store brand fudge stripes are terrible! They're like fake chocolate flavoured chalk!
I don't like supporting brands in general, and don't often go for these (lil cookie/biscuit thingles with chocolate on the bottom and striped across the top) but only the name brand is tolerable :-\
Shoes! I buy expensive brands lightly used via ebay. So I spend the same amount as I would on a shitty pair from a random department store, but I buy Magnanni (best sneakers EVER), Allen Edmonds, etc... They last for years instead of months.
Generally I'd pay a little more for almost everything, unless I'm absolutely sure the cheap thing I'm about to buy has been a staple in the community and got recommended a tons. I found midrange priced stuff to be the sweet spot that give you a lot more quality and longevity compared to the cheap stuff, while not landing on the other end of diminishing return and overpay for something that's overkill for my needs.
Television. I absolutely cannot stand TVs with bad picture quality. I look at it for hours every evening so it’s worth it to get something that doesn’t bother me.
Steaks. But still in a cheapish way. I was thoroughly disappointed in a ribeye I ordered at a restaurant once. Since then I wouldn't order one of those in a restaurant, but I will buy my own. Ribeye is my go to. Sous vide is the cooking method. Cannot be beat.
Everything that is used daily and has a big workload like fridge, dishwasher, washing machine, vacuum.... Car parts... As mentioned before: computer parts.
Also cosmetics: find out what your skin needs, which products are the right ones for you. Don't clutter when it comes to cosmetics. Buy only what you need but good stuff.