Perhaps over time we get more choosy and instantly dismiss WGs that aren't ticking all the boxes and have stood up to close UKP scrutiny, a quick search locally on AW brings up two pages within easy travelling, spreading the net to 25 miles gets me 6 pages, although after weeding out the Romanians, the ones that haven't been online for a month, the BBers, the ones that UKP screams "AVOID" and the the fat and the ugly there's only a handful left, but still more than should be enough.
Having said that I've had a couple of times I've fancied a punt over the last few months, trying to book the day before and either finding that I'm not even getting a reply to my emails or that the girls I was after are not available at the time I was free.