Vegan restaurants exist for a reason - people like having more than one option when they go out. Imagine getting basically the same burger wherever you go because that's the thing on the menu you can eat. It's better than nothing but it gets boring really fast.

The number of vegan restaurants compared to the actual demand right now is too high though, especially fast food vegan places that can't differentiate themselves well because they all use the same substitute products without doing much to them.