The #1 feature of a CC is the fraud protection.

If my credit card gets stolen, the criminal has access to the bank's money.

If my debit card gets stolen, the criminal has access to my money.

Just don't be an idiot like me, have your credit card at the same bank that you have your bank account at.

Then have someone steal your card info, spend lots of money, and then use the vast legal resources of eBay to fight your fraud claim with piles of paperwork.

I've found the fraud protection of CC quite lacking. Bank puts up no real fight to the counterparty appeal of the charge back and then you're fucked, especially if the bank already has your assets. In my case the appeal was from some guy with literally 'pirateArrrggh' in his email address and they stated it absolutely must have been me. My bank literally laughed at me and insinuated I was a fraud for daring to claim I couldn't have been the buyer of religious and women's beauty products as a straight atheist man.

Not everyone has as much liquid capital as you do. Short term loans can help cover necessary expenses (broken AC, car, etc) for those with less means.

Taking these loans for someone without my means is even worst idea, because the interest payment will hit them more.

And I mean, broken AC is not necessary expense. It is a luxury item. A car may be necessary expense if your place don't have public transport, but at least here, poor people don't have cars.