no quotas
no commissions
where the money goes: into the budget that funds the city, county, and/or state
ALL convictions whether they are traffic tickets (class "c" misdemeanors), class "b" misdemeanors, class "a" misdemeanors, and felonies have a fine and court cost attached to the conviction. (and a time sentence too, but that has nothing to do with money) the court costs go to pay for the cost of using the court. each state has a different system for deciding where the money goes, how it is split between the county, city and state.
the reason your taxes aren't higher is that revenue from those convictions pays for roads, bridges, trash pick up, crime victims compensation, crime stoppers, restitution (for thefts, fraud, investigation costs like lab fees), office clerk's, police equipment/salaries, judge's salaries, schools, teacher salaries, state funded programs (like department for the blind, department for the deaf), etc etc etc. But the main idea behind court costs is to put the cost of using the court on the backs of the people who are using the courts: the defendants.