In case anyone else wants to "call BS" on this:
https://www.americanbar.org/groups/crsj/publications/human_r...
https://www.americanbar.org/groups/crsj/publications/human_r...
But I honestly don't see the problem in principle.
If a court issues you a fine and you simply ignore it, that's not a situation society can just ignore. If you are truly unable to pay, that's more complicated, but should not just simply magically resolve you of responsibility.
There has to be other measures to ensure that money is paid or an equivalent cost is beared. Garnishing wages being an obvious first step.
(This is especially true if fines were to scale with income/wealth)
Not paying a fine? You committed a crime that led to the fine. The not paying is an after effect.
Making anyone who jaywalks go to jail is a miscarriage of justice.
Basically what happens is that often the court makes a poor determination of how much a person can afford to pay each month, and when they can't make the payments they are jailed for contempt of court (for violating a court order). Often the first thing states do is take away the person's driver's license as a warning before jailing them. This makes them unable to get to/from work and usually results in their unemployment.