They probably are sailing close to the wind but then who is going to bother suing them? Is any wannabee daft enough to take legal action against an airline for discrimination and then expect another carrier to take them on after they have a history of litigation? And lets not even discuss what the costs would amount to.
Whichever quango polices the discrimination laws probably has much better industries to get its teeth stuck into to keep themselves busy in the courts for years without delving into aviation.