I feel very confused.
1) Do you have money to pay for your own coffee? Do you usually let others pay for you?
2) What the h*ll does the 7th tradition have to do with coffee after a meeting?
I felt your post was confusing to understand in the way you explained everything, but I will say this: it's rude to let people pay for you all the time. You shouldn't agree to go out for coffee if you don't even have a couple of bucks to contribute. Nobody owes you a coffee. Don't go for coffee after meetings anymore if you can't pay for yourself. Also, it sounds like you were sulking, which was probably very annoying to everyone else.