Well, what benefits does it give ?
It's pretty badass to be the center of Dwarven civilization.... but on the other hand, this will attract attention
Hm... Well, attracting attention should be fun, right ?
Do it. We deserve it.
Of course we accept it, a massive reward for your excellent leadership skills.
The benefits are mostly that the King and/or Queen moves here (and starts issuing mandates, such as "Make a platinum toilet for me!").
Other than that. it's largely just prestige.