Herren and WHAT!?!

At that restaurant the other night I had to go, so did what a girl's gotta do. I went for the loo. Once I've located the right direction I passed the "Herren" and was expecting the next door to say "Damen". As one does. Imagine my surprise when it said "Horses". WHAT!?! Nearly had a fit there and then. Men are referred to as Herren, and women as Horses? Excusez-moi! Was gonna take my business elsewhere until I spotted a door on the other side of the corridor, saying "Damen". Phew! That was a close call, before I'd have had a serious shout at the staff. But I still wonder why "Horses"? It's not like they had a stable there...