Pretty much, yes. However poor people, or people living paycheck to paycheck, are much more likely to pay those fees, esp. the high credit card interest which sometimes is not voluntary (e.g. emergency medical or auto repair expenses that need to be paid for somehow.)
for instance, maybe 10 years ago I got a fix-it ticket for a cracked windshield on my car. It wasn't dangerous (despite what the officer said) but I had to get it fixed somehow. Because my car was older and uncommon, a new windshield was $500ish, and because I'd received a ticket that had to be cleared within a week, I didn't have time to call around to a bunch of junkyards to find a used one. I didn't have $500 in my bank account. What's the solution to that, other than a) drive illegally or b) use credit card? (I'm doing much better financially these days, thanks for asking...)
Now whether that is fair or not to charge high interest rates to someone whose only fiscal fault is not having a considerable amount of personal savings, that's another discussion. Personally I think it's far better to try to make oneself indispensible at work, advance to a higher paying position while not greatly increasing one's personal expenses, etc. but like I said, that's a separate topic.
nate