Its not a matter of being stupid.
Some people have a moral objection to debt and usury.
Its like drinkers saying everyone should drink, smokers saying everyone should smoke,,,, some people simply choose not to.
This is about making money. It's like not using a tax advantage - you're basically tossing away free money.
If you're irresponsible with your ability to say "OOOOOOO I CAN CHARGE $3k for a brand new expensive ass brand name suit right now!" and somehow not resist - you have mental problems.
The reason debt exists is because there is profit involved with interest payments (1st) and secondly, it exists because people do need help on occasion - and sometimes there is no other answer. I still can't fathom how you find debt to morally wrong - given it is used for helping people. The fact that some people use it wrongly and have consequences isn't the fault of debt.
I have over $30k in liquid assets, as well as retirement funds and other items I can pull from. Do you think I'm charging to a credit card because I want to be in debt? Hell no, it's because that $30k is sitting the bank an extra month for earned interest. The credit cards are earning 1-5% cashback on all purchases, and the credit cards are giving me support in case there is a problem with a transaction.