Cracking and sending it in again is possible, although I think the vast majority of thieves want a quick payday and would not be willing to invest money and wait the months or years (backlog) for grading.
There's people who like to buy graded cards and "liberate them from their prisons" to be played. The whole collectors' grading system is insane. See also: the massive fraud in video game grading by Wata and Heritage Auctions.
Of course companies wanted people to share the free demo versions but some full games did have annoying protection schemes in the '80s. Obfuscated data and purposely "bad" sectors on floppy; cardboard decoder wheels; asking for word #x from line #y of page #z of the game's manual, or, similarly, a page of codes printed in black ink on dark maroon paper to prevent photocopying... leading to folks distributing cracked versions and the cracking tools themselves!
To be fair, it was a pretty ridiculous time. Computer club meetings just turned into floppy-copy-fests.
I had a boomer drop off a laptop after Win7 got updated to 8. Post-it note read: "I'm used to Windows with the "e". Is Windows even on here?"