And Googling 'Kronenbourg' and 'pint of numbers' threw up this nice little anecdote (which I have very gently subbed):
I once worked as a barman and this lad ordered a pint of "numbers" with a male colleague of mine. The barman who was working with me didn't respond to this chap's request. The customer, thinking he had a cool way of ordering his preferred tipple, said: "Haven't you heard of a pint numbers before, pal, what sort of barman are you?" The barman replied: "Yes I have, but we sell 80 Bob as well." Needless to say, the smile was wiped right off his face.
Apparently, 80 Bob a Scottish beer also called 80 Shilling, or sometimes 'Caley 80'. There you go.