It also sounds like they would already have one, and / or that it would be relatively easy to move if they want or need to. Don't they go back to their more rural homes for special events, for example?
Moving a ger can be a significant effort, especially a large one. Most urban dwellers find owning the trucks and vans that can hold these things pretty impractical if they're not moving regularly.
There's a fairly large domestic tourism industry catering to urban city-dwellers who want to go live in a nice ger for a couple weeks to feel connected to their history.
