I all honesty I do not transport because the risk, cost and added work is just not worth it to me.
With that said, if I did transport and a parent refused to sign the agreement I never would have accepted them into care.
If, as a parent, you choose NOT to have your child transported...then choose a daycare that does NOT transport.
IMHO, It is unfair and selfish to expect a business to change their program to suit your wishes over the other parents.
If your child's class is going on a field trip and you don't want yours to go... Keep them home.
Maybe some centers have another person available to keep kids that have been left behind...maybe choose one of those centers if you know it is going to be an issue for you.
Pick the appropriate daycare for your needs and wishes. Don't try to change the program after the fact.