I know somebody who does this. He’s an older middle aged man like me. He’s widowed and wanted a woman in his life after his wife died. He told me all about their arrangement. He helps her pay her bills and support her family. I’ve been out socially with them sometimes. They interact like they are boyfriend and girlfriend. Though she is a good bit younger than he is, you would think they are just like any other couple.
Based on what I’ve seen, I would say that there is more to what they have going on than just sex. But, would also think that there would be nothing going on with them, if not for sex being part of their arrangement.
So why are they not married? It’s easy enough to do and eliminates what little social sigma remains as well as getting it right with the Lord.
Let's put it this way: He is the one for whom "no sex" would be a deal-breaker, and she is the one for whom "no money" would be a deal-breaker.
That, in public, they can interact in a civil and maybe even friendly fashion is meaningless - people can be polite towards, joke around with, and even display sincere kindness towards: Their cabbies, barbers, shoeshine boys, elevator hops, etc.
Regards,
The Girlfriend Experience