@Apollo'sJest This question presumes that the alternative to government-monopolized roads would have to produce an outcome very similar to the status quo in order to be acceptable. Is that really so? Part of the libertarian proposition here is that government is terrible at serving people's needs, often doing the exact opposite of what would have solved the problem. The market may come up with a transportation regime quite different from what you see today.
But for the sake of argument, let's assume the market produces the same outrageous sprawl of roadways the government produced...
Would tollbooths be installed every 10 miles?
Do you make micropayments to different ISPs every ten minutes on Netflix? No, the various firms involved in bringing the content to your home across thousands of miles of wire have negotiated with one another ahead of time. You pay a flat rate to one service provider, and they handle the other complexities for you. This is capitalism, remember. Everything revolves around making it easy for the consumer. Tollbooths at every intersection would be idiotically inconvenient. In the same way the market can present to you a pencil -- whose ingredients came from all corners of the Earth -- for a single low price, the ability to travel far and wide can be organized and sold to you as an easily digestible commodity as well.
