Fair point and pretty disgusting when you get a whiff of a smelly minge, in civvie life as well as from a WG. Trouble is I imagine once you've paid your money (even after confirming what's on offer up front) there's very little way in practise to get your money back, when you're both starkers and you just come up from buried between her legs saying "sorry love, you stink, I want my cash back). I can imagine a lot of punters being pretty unwilling to broach that subject (especially given as a country of reserved brits we will complain to our mates in a restaurant then when the waiter walks up "no, everything's fine thanks very much"). Not right of course but that's how a lot of people are.
I've never experienced it myself, always found WGs to be really clean but I imagine if I did I'd just stop the RO/69 whatever and concentrate on getting what I want out of the punt. I'd love to be more brazen but I'm not sure I could stop at that point and demand my money back.
KV