I organise gigs for charity and personally make a loss every time I run the night as I don't claim back the limited expenses I have. An unnamed venue have decided to make a night am putting on in week or so 'free.' There is still a door charge but if you had gone to the bar downstairs and collected a card then you can get in free.
I am thinking of 'doing a Radiohead' and having a voluntary contribution box to get round this. Would you pay in any money assuming you were coming to the gig anyway before the 'free' business was announced?
If it helps the charity is Oxfam and the gig would have been £4 for four local bands.