I didn't meant the actual cost (as in Dollars) for the infrastructure but the associated disincentive. Collecting toll would certainly increase tax justice by relieving the general taxpayer. But that wouldn't solve the traffic problem because people will still need to travel somehow.
Roads are enormously expensive both for construction and maintenance, and in most places AFAIK fuel taxes and vehicle registrations do not cover that cost, so they are being subsidised by the general taxpayer.