Re: it makes sense
The problem is that people have heard about these underground beer aquifers and misunderstood. This is why so many pubs connect the large plastic pipes they find underground directly to their lager pumps. Not realising that these pipes link to the outlet of their urinals. Fortunately no one has yet noticed...
But there is a reason why there's a whole section of the 1999 Water Regulations dedicate to the correct marking and colour coding of pipes.
The interesting question is which came first. Was it the belgian chocolate miners who first stubled across the beer wells? Or was it people drilling for beer who found the rich seams of chocolate to mine? Bruges is certainly a rich source of both.