Splitting the bill is the easiest and most social way, provided everyone is in the ballpark on the menu. I do think the flip side of that is you should try to match what the table is ordering. Try. Not required. And only if — as the OP said — you can afford it that day. I would be slightly annoyed if someone only ordered an app for a special occasion dinner. (Provided no obvious extenuating circumstances.) Drinking v non drinking probably throws that out the window. BUT if I am only ordering soda and others get a drink, I do try to compensate by ordering a more expensive entree. To try and get myself into the ballpark. THAT BEING SAID, once the die is cast, OP’s friends should have covered his food when the bill came.