Free WiFi

In a pub, at the bar.

Customer (pointing at the "Free Wifi" sign): What's the password?

Barman: You have to buy a drink first.

C: Fair enough. I'll have a pint of lager.

B: Foster's, Carling, or Carlsberg?

C: Carling, please.

B: Here you are. That'll be £3.

C: Thank you (pays £3). So, what's the password?

B: "youhavetobuyadrinkfirst" All lower case, no spaces.