The use of the I pass is an add-on. if you don't pay for it as part of the rental, but to use it, then Budget charges the going rate. At least now, they are telling you in FL that you will need it and can't pay cash at certain checkpoints.

I would assume that the discounted price given on the toll that Budget pays and that you eventually pay is mostly profit although there is probably a monthly fee for the use of the I pass.

Agree it's annoying, but I doubt you will have much luck fighting it. If you are successful, I want to copy off the smart kid, so please post your paper!