My local:
12 year old: Can I have a pint please <Hands over money>
Barman: <Pours pint> It's for your dad right?
12 year old: No its for me.
Barman: I can't serve you so its for your dad isn't it?
12 year old: Uhh...
Barman: Yes its for your dad. <Hands pint and walks off>