I agree with you entirely on the possibility of being able to save money by calling and negotiating, but if I'm evaluating two options, and one shows me pricing and lets me sign up without talking to anyone, and the other will require a phone call, I will most likely not be calling and giving that company any money.

This is, of course, one of the many reasons why I don't run a large, VC-scale business. I don't have the patience or desire to play these sorts of games.