Sure they do -- but once you introduce at least one custom component (i.e. hexagon map), it's actually not straightforward, how to integrate it with the rest of the controls.

I can't say whether it's me who's stupid, or it's just not very easy to make good UI in game engines. I don't say that's not doable of course -- i'm just saying one would need to invest quite a bit of time to work out how to do this.