People should not go directly to jail if they fail to pay their fees on time. There are events that can prevent people from paying immediately and on time, mistakes and accidents occur and they will be in jail soon if they fail to pay the fines and fees they are due.
No, I do not think people should go to jail immediately if they cannot pay their fines because some people don't have a stable source of income and quite honestly have no money to pay the fines. I think that there needs to be some sort of warning or payment agreement to ensure that no Americans gets jailed for failure to pay fines.
I think that people should be given a small grace period if they cannot pay their fines. Sometimes people have to take a few months to acquire the necessary funds. Overall the funding for people is iffy, so any possible grace period would be much appreciated. The debt collectors are all evil anyway.
Jails are way too crowded to be able to take in people that cannot pay fines. Jails should be reserved for criminal activity. Unpaid parking tickets and other civil fines do not rise to that level. It would likely take more taxpayer money to jail those people that the payment of the fines would even bring in.