> Why would companies be building roads like that when there is no need to do it?

Need is a poor way of looking at investments. Having a more direct route reduces travel costs. Which is while people use Toll Road‘s even when their are generally other options.

If you want to make the suggestion that companies will make toll roads you need to explain why the don’t even when their are many profitable bridges etc. Toll bridges could be profitable in many places yet they are not built largely becase the cost is so extreme.

I meant that in the US everyone expects the government will provide roads, and there are already many good roads to use for free (eg the Interstate Highway system).

As a result, people are not willing to pay much for more roads, so they aren't going to be built. It may not even be legally possible in many cases under current regulations.

Being US specific is not meaningful when it does not occur in any country.