After an electronic system is put in place, tolls start rising
sharply. Take two tollbooths that charge the same fee and are in a
similar setting – both on highways leading into a big city, for
instance. A decade after one of them gets electronic tolls, it will be
about 30 percent more expensive on average than a similar tollbooth
without it. There are no shortage of examples: the Golden Gate Bridge,
the George Washington Bridge and the Tappan Zee Bridge, among them.
“You may be less aware you’re paying the toll,” said Ms. Finkelstein, now an associate professor at M.I.T., “but you’re paying a higher toll than you used to.”
Here is the full story. One thought is the Brennan-Buchanan government rapaciousness angle, layered on top of behavioral imperfections. This result is also why electronically extracted tolls might reduce congestion less than we would expect; they’re not sufficiently noticed. Mark Thoma suggests some other interpretations of the data, namely that the electronic toll, by lowering traffic, inconvenience, and queuing to pay tolls, allows the highway authorities to raise the monetary fee to restore the previous net price.