Yes. We have a glass tabletop, so without placemats everything is loud and could scratch the table. Upside of the glass tabletop, aside from the look, is cleaning it is super easy with glass cleaner (not Windex).
Yep we use placemats in our house. It was the first chore we ever gave to my daughter - to gather up the placemats after dinner and put them away in the drawer. I'm 37 by the way.
I'm trying to remember what it was from where a dude is eating cookies in bed, gets some crumbs on the sheet, then just pulls out a mini vacuum cleaner from his night stand and cleans it up.