Yup, used them too.  I've even seen a card get Snapped in two in one!  That was a very unhappy customer!

We used them at a party supply store for deposits on costumes and helium tanks.

Wealthy investor guy rented a tank and never returned it, we hit that card for $20 every week for months.

The police department eventually  returned the tank, evidence tag still intact. He had lost everything in the market, he and his wife killed themselves in their car overlooking their multimillion dollar estate by inhaling the helium.

I don’t think we rented that tank out again.

Newer cards don't even have the raised numbers anymore, just the chip and printed numbers on card.

New cards don’t even have numbers. A strip, a chip and a name. That’s all you need.

Yup.

Back in the day (1980 or so), we had a TINY little booklet of "bad" credit card numbers that we weren't supposed to take -- about 3" x 6" and maybe 100 tissue-paper pages of card numbers.   These days such a booklet of bad cards would be encyclopedic in size.

And yes, hand-writing all the credit card info directly on the carbon was the way it was done if the card wouldn't emboss properly.   Some cards had their numbers flattened from overuse and we had to hand-write them.  Other times the "frip-frap" embosser was broken and hand-writing on the carbon was the way it had to be done.

Or its rival, BankAmericard

Yep, me too. I’m sure it’s still there.