Tolls are regressive and will have a greater impact on poor people who have to commute to work. Second, public infrastructure is paid for by by both taxes and use fees/licenses/fines. That's a bit different from a utility. If the feds and state gave me back the money for the roads I've already built, I'd be fine switching to a pay-as-you-go model. Another consideration: This state is already funneling too many public funds to private toll road operators — to the tune of billions of dollars. I'd really hate to see more of my money go to people who are already charging the public way too much for setting up booths on the roads I paid for and charging me to drive on them.
As a side note, I've always thought California was leaving some big revenue opportunities on the table by not issuing special licenses for high-speed driving and creating high-speed lanes for people with those licenses. It would be a neat experiment. We could try it out on the 15 between LA and Las Vegas, were people are driving 100 anyway.