Most reputable venues expect to pay more over the Xmas & New Year period and rightly so! On average with bands and solo artistes we usually end up paying a bit extra for Xmas week itself, Xmas eve's always about double the normal cost and New Year a bit more so. Politeness usually throws a couple of free drinks their way also.

I guess it'd vary from one venue to another but why should a club be rolling the cash in over Xmas and the staff/artistes helping to bring it in not see a penny of it?