Yes, I saw your point Keith. But my point was that my choice of festivals partly depends on the sessions available.
So the session players are indirectly supporting the festival by bringing in people like me. More so than the expensive 'big names' concert performers that the festival books to attract the people who like to watch them all weekend. And the Morris teams that might attract others.
Room for everyone. (And Whitby sends collectors round to rattle tins at people enjoying the pub music and outdoor displays).