Re Broadstairs- There has been a singing session every evening for years in various venues & plenty of opportunity to participate. Looks this year as if the venue will be much better if all goes according to website! As Dave B says, problem in the past has always been two-in-a-bar rule for pubs- for me one of the joys of festivals is striking up with new musicians, which takes place informally on campsites & in rooms, if the landlady is agreeable. It's a very friendly festival.