"if the paid-for festival dies so does the fringe. If you want to do fringe things it's still a good idea to help support the parent festival. Simply buying drinks, food and accommodation doesn't do that."

Likewise - If the fringe dies so does the festival (they are co-dependent); the very high numbers of folks attending the Whitby festival is testimony to the success of both - they should not be seen as being mutually exclusive. It's not a question of one half attending the parent festival and the other half attending the fringe festival; clearly there is considerable cross-over. It could easily be argued that the fringe provides the essential support to the parent festival!