TOareaFan
Superstar
If the question you're referring to is in the last paragraph, then I would say it depends. It's true that the demand is pretty inelastic in the short term, but in the medium to long term, people will make decisions about where they live and where they work that would tend to reduce or eliminate the time they need to spend on highways during rush hour. It will also affect where busiensses decide to locate themselves, as requiring your employees to drive to a suburban office park would probably require some incentive through increased salaries to offset the transportation cost to the point where the company might decide to locate in a more accessible area.
I agree the whole free/prepaid business is pretty irrelevant to the goal of changing behaviour.
Actually the question was in the first part:
is the goal of road tolls to end/reduce/limit congestion? or is it to raise money?