The food and showers are a good deal with Shelter. You get more vouchers than Oxfam does. I personally don't mind working hard, you know its going to be serious graft, but when the paid Avalon staff sit in the back drinking with their friends all night and letting the volunteers deal with never ending queues, it verges on taking the p***
Sounds like you were in a better managed bar which is good. My first year wasn't bad either. Just luck of the draw I guess!