I don't know... Whether I felt I should buy a drink (although I probably would anyway) would depend on door charges. Perhaps I'm one of the tight ones but the last pub venue I paid at I think tickets were £8 - so it cost me £16. I'm not going to feel obliged to buy a drink on top of that,
Anyway, I'm out for free music (and a couple of drinks) tonight. I've heard of one of the pubs I go to for a session having a regular night of what sound like music hall songs and other older popular songs and thought I'll have a look in. Will probably move on to a session from there. I'll buy a drink there but in this one, those that play do get a free drink at the end of the night...