I find guest performers,who sit outside the clubroom,and only come in for their sets ,rude.
a couple of years ago I was booked in a club in Clonakilty,with two fiddlers.In walked a Dutchman with a dozen harmonicas,he proceeded to join in every tune when he didnt know the tune or key,the harmonica sounding rather like a concertina,from my point of view was very distracting,when I asked him to stop as it was off putting,He got very agitated and started shouting and swearing.
   I looked at him,and he ran away.