How is that an innovation? You're describing Charge Cards
Charge cards generally force you to pay them off each month (again, an Amex charge card expects you to clear out the balance for each cycle). This is a credit card, which means you can carry a balance.
At least in the US, charge cards also (historically) charged higher fees to retailers, so a lot of stores wouldn't accept them.
Given the rates charged by many cards, I'm not sure you'd want to do that. The US has an average of 15%:
* https://www.creditkarma.com/credit-cards/i/average-apr-on-cr... * https://www.valuepenguin.com/average-credit-card-interest-ra...
You can't really compare it to mortgages or car loans, because those are both secured by a collateral. You can't really compare it to student loans because it's impossible to get out from under a student loan. Either way, the debt is less risky for the lender, so they're willing to offer it for a lower rate.
Never for truly big ticket items, but sometimes the $5 or whatever in interest to carry a small balance for a month isn't worth the extra effort it would take to free up the cash I'd need to pay it off in full without dipping below the minimum balance I like to keep in my checking account, and it's also not worth $5 to me to wait another month before replacing that busted transmission.
It depends on the matter of scale. Some folks either don't understand how things work, or are just bad at math. That's where the problems start for people.