Customer: A bag of chips please.
Server: Do you want salt and vinegar with that?
Customer: Yes please.
Server: There you are sir, £51 please.
Customer: £51? £51? You’ve made a mistake! It’s just a quid for a bag of chips.
Server: Yes, sir. And £50 for the salt.
(A weather joke originally, but since ‘salt’ also means a decent girl in street speak, this joke is multi-functional in its appeal!)