[PKop]

Ok monopoly was absolutely the wrong characterization. They are a cartel. ("an association of manufacturers or suppliers with the purpose of maintaining prices at a high level and restricting competition.") Which is a difference of degree.

But your analogy doesn't make sense to me. There's not political or regulatory reason there exists one coffee shop.

And because of this fact, if they abuse their position as the sole coffee shop (raise prices, provide bad customer service, etc.) they will open themselves up to a challenge from another entrant into the (open and free) market.

This is exactly why taxis are a different beast. They are protected from competition. Explain to me how taxi cartels operate in a free market? Or conversely, if you agree that they don't, explain how coffee shops operate under the same conditions?