I have a very weird story to add to this discussion. I had a friend visiting from England. We were in our mid-twenties at the time, so were of legal drinking age, but young enough that it wasn't absurd to wonder. We went to dinner, not intending to have a drink, and she left her passport at home. She ordered the tequila prawns, and the waiter asked for her ID. We were surprised but explained the situation (from another country, no driver's license, passport at home). He refused to bring her a dish cooked with alcohol in the sauce without proof of age. We ate elsewhere. That seems like a crappy waiter abusing his authority to me, because I can't imagine even the most zealous cop enforcing that law (no wine reductions for anybody under 21, for instance). I don't know the law in NYC, but in Oregon, where I used to live, many pub/restaurants got fined regularly in undercover sting operations. They would send in underage kids to order alcohol, then fine the restaurant for serving them. If NY's law is the same as Oregon's, it isn't just the minor who is breaking it, but the restaurant owner as well. I would understand a policy of not serving minors under those conditions. However, if the general practice is to ignore the law, and the server went beyond the policy of the restaurant, I would be pretty upset.