yes, people CAN buy a tile, and everyone who hears about it AFTER their car is stolen goes "that's a great idea, I'm going to get one with my next vehicle". people tracking their cars only deters crimes if a significant portion of people have tiles. if you just wait for people to buy them on their own, most people simply won't because they don't know they exist, assume there is a subscription, or are otherwise unsure. if you give all car owners one, then they will try it out, see how it works, and will spread the word.

the trash cans or recycling bins could have been given out to only residences under a certain value and tell everyone else "hey, it's better for you and everyone if you buy a $100 can" but people wouldn't have bought them. some things have to be done all at once and across everywhere to work.