If they are not going to pay for transportation, then they should pay another juror who is close to you to drive you in for jury duty. Usually, in some areas, the legal system used to pay a per diem(for meals usually), I suppose, they don' t have that for transportation, in this case as they did not tell you.

When they send out notices for jury selection, they sometimes get more people than they need. Hopefully, that will happen for you. Or the case that to go to court will be settled out of court. Unfortunately, all the candidates for jury duty may have to be told this when they show up to be selected or not.