Again most people can’t afford the up front cost.
Its expensive to be poor, and most people are poor
They are already in debt paying huge amount of interest monthly.
I like being able to charge at home and it’s a luxury I know not everyone gets.
For the numbers:
Paying off a $600 charge at $10/month like you suggested would take almost 13 years and cost over $900 in interest at a 18% apr
So you are spending almost 50% more on interest than the original charge. So 150% more expensive at 1500 vs 600.
For a 5 year payoff you have to spend just over $15/month but still are paying over $300 in interest. That’s now over $900 total or 50% more expensive because you can’t afford the up front cost.