How about if the road company threatened to put speed bumps on the roads unless the restaurant companies paid to not have them installed, and Burger King paid but McDonalds didn't? Oh, and you already paid the road company a toll to use the road to drive to the restaurants in the first place.

That's much better.

But now the reply could be:

"The customer is free to choose a different road company. And the road company is free to choose its business model. The free market will decide which road company offers the best price/performance ratio in the end."

(again, devil's advocate)

But in the US the average consumer doesn't have a meaningful choice between road companies: http://arstechnica.com/business/2014/09/most-of-the-us-has-n...

This is the heart of it. Free market economics is a wonderful thing and as a civilization we have reaped enormous rewards from it, I'm a true believer, but if your market produces natural monopolies that are highly stable then that's not really a market anymore and it's certainly not free or fair.

Adam Smith, the father of free market economics, was very clear about this. Markets must be well regulated in order to remain free and fair.

thats not devil's advocate as much as it is a "racketeering advocate" [1].

[1] Racketeering, often associated with organized crime, is the act of offering of a dishonest service (a "racket") to solve a problem that wouldn't otherwise exist without the enterprise offering the service.

And because roads are expensive, there is only one. If you don't like it you just have to fly your helicopter to McDonalds instead. The market works!