A credit card is not automatic debt. It is a line of revolving credit. Think of it as an abstraction on top of the money you already have on your bank account. Additionally, credit cards provide additional protection, such as fraud prevention and charge backs. Yes you can misuse them but... Don't?
Edit: I guess a better way to phrase that is that a credit card is the ability to take out small short term debt in real time. And potentially pay it off for free.
The only thing I have to do is pay the bill in full each month. I can't imagine letting people have access directly to my bank account.
1. Yes, the US system overall is less than ideal. Banks could take initiative to simplify the system and the consumers probably should demand that they do.
2. American consumers are not somehow more stupid than people elsewhere. Introduce the same incentives elsewhere and people will follow the same pattern. The only reason other countries seem not to get into as much personal debt is mostly because loans are not as widely available and ones that are cost much more. In the US this used to be the case during the majority of the 20th century. Since relatively cheap credit became available, americans started taking advantage of it. This has nothing to do with whether they are smart or stupid.
Moreover, I think the grace period it still a debt even if it carries no interest, it's the bank tempting people. You can still accrue it more than your account size, it's still borrowing without thinking about what the revenu the spent money will bring.
Debt is a financial tool like others (like selling capital for example), but I really think its use should be restricted to productive investments, and its overuse is a big problem. It's a useful dangerous tool, like a chainsaw, if you're not a lumberjack there is not reason to use it everyday, but it's practical if you make your own wood.