That isn't always a scam actually. A lot of old fa^W men retire and marry a citizen to secure rights to the land under their house. I have seen a lot of that (entire gated communities) and it all seemed long-term and high-commitment and in a good faith. Ones on the younger side of their 60ies mostly have a business of some sort and kids together too.

I don't know how much love is there in these marriages and don't draw any judgement either.