My own experience of sessions and singarounds (in the UK, not Eire) is that musicians and singers are not there primarily to entertain an audience but are there because they love the playing and singing. However, when you're in a crowded pub and there's a group who feel that they're an audience, they don't understand that you're not there just to entertain them, so they continue to act like an (appreciative!) audience.

So – I think it's a misunderstanding caused by a clash of cultures. Somewhat irritating but pubs are, as the name suggests, "public" places..

Fair comment, I reckon - though, as a mere Irishman, I'm never quite sure where Eire is when the term is used by English speakers. Is it near Tír na nÓg? ;>)>

Regards