Often visas - either that they cannot get visas to live or work in a different country, or because leaving the US would cause them to abandon potentially decades of progress towards permanent residency.
I've been actually - considered staying - and if you haven't I'd highly recommend it. Especially a day trip up to Pyramiden. While you do not need a visa to stay in Svalbard forever, you do need a Schengen visa to get there which not everyone can obtain!
