Sorry Exedus, but I disagree. US toll roads function to generate revenue for maintaining the roads, not to generate profit. 

Under an investment bank approach, the infrastructure investments must generate a large return to compete against other potential investments. And there will be an expectation that the return increase over the years. Why would a company or investment fund make an investment unless they get a return on that investment (while passing over other investments promising a large return)?

You cannot implement a market competition approach and then suspend the 'laws' of market competition.