I go out to dinner once in a while with a group of friends. We started doing a little fun thing where when the check comes, we ask the waiter to choose from one of our credit cards and whoever’s card the waiter chooses pays for everyone’s meal.
Is this considered gambling/assur?
You are correct. It is a sort of gambling, and if you are the loser, you really don’t want to pay for everyone’s meal. I would suggest that you have a rotation, that each person pays once in a while or that you should take turns offering to pay.