I don't! They aren't! I wasn't! Nobody does that because they cost (at least then) several dollars.

The point of my anecdote was you use a bank check once and you learn about scams and laundering money, so you don't "run around casually" using them.

Probably there are more high schoolers "running around casually" with credit cards than there were 25-30 years ago, but in any case I didn't have one.

I certainly never again tried to use a check that wasn't for an exact amount.

By the way, some people do or did use personal checks at the grocery store and get cash back - I don't know if you can still do that and I never have tried it, but it used to be a thing.