I hadn't thought of this angle. I will say that when I stay with a friend (early 20s) it's typical to bring beer/food and buy the other person dinner/a meal alr

I hadn't thought of this angle. I will say that when I stay with a friend (early 20s) it's typical to bring beer/food and buy the other person dinner/a meal already. I think some people could circumvent the system- but many will be happy to avoid the etiquette questions and just pay a friend-of-friend.