In Swartz's case, putting someone in prison that is contributing to society in exchange for locking them up for 30+k per year seems completely backwards, cruel and ancient thinking. A system that can create larger criminals easily from imprisonment of minor or non-violent actions. We should at least differentiate them better.
Martha Stewart was jailed for insider trading. Before, during, and after, she has a much more comfortable option for her life than to join a gang.
They stole from you and harmed you economically. If they go to prison your tax dollars and the tax dollars of others must house them, pay for their care, etc so they are further harming you economically.
It would make more sense to have them provide restitution to you in some form. They should have to pay for:
Damage to the car (if the car still exists) + cost of you not having your car and any sort of issues arising from that (i.e. you were on your way to an interview, you came out of 7-Eleven and your car was gone, you missed your interview and now have no job, or some such) + interest on the previous two things they should have to pay for
If they destroyed the car in some manner then replace the first part of the equation with the cost of a replacement car of equal value.
Prison should be used when someone can cause harm that is permanent such as murder, rape, etc to prevent them from doing it again to someone else. If they harm is just economic in nature then that can be rectified and there is no sense in making everyone pay to house someone who did no permanent damage.
Further more as pointed out below, going to prison tends to make people come out worse criminals.