Here in California, jaywalking is an infraction, not a crime. Jaywalkers (who are caught) have to pay a fine. It can basically be considered getting sued by the city for breaking the rules.

If you can't pay the fine, it can turn into a warrant that can get you arrested. Thus jaywalking actually is a crime, but only for poor people.

> If you can't pay the fine, it can turn into a warrant that can get you arrested.

Technically, inability to pay does not have this effect, only refusal. But you have to actually show up to court (as specified in the ticket, which is a summons to appear with bail that can be forfeited in lieu of appearance) and assert hardship to get a different penalty or payment arrangement set if you are unable to pay; if you just ignore the summons and don’t pay the bail set, then you are committing a crime.

And if you are significantly poor, missing a day's work to show up to court can cost you your rent, or your job, etc.

So it's still a crime for poor people only.

That is why you put it in writing and mail it to court.