I think quite a lot of people play for nothing for the same reason that they do the lottery. Perhaps less in the folk area.

If you get to the realm of 'being famous' and in demand then the rewards are huge. The chances are tiny but why not?

My son plays in a good band (radio plays - decent album - won £6k to play in a rock festival in Canada etc - ) but most of the time in London you play gigs on the basis of 'how many friends can you bring?' - you pay to play. The bigger your fan base that you can drag to gigs the more you earn. But if you play functions - as Will and others said - you can earn money. Whether it is what you want to do is a different matter. I've recenntly started to play with a guy whose agent used to book him into all over the place and it nearly exhausted him as he had a full time job too!

Most of my friends who make money from music make it from busking (up to £100 an hour) and playing ceilidhs (£300 - £500)

I played in a £150-£200 covers band a few years ago. After costs/travel/strings/etc etc it's not a way to get rich but it was enjoyable and easy. Rough rule of thumb I was given by pubs was they needed to generate 4 times the fee to make it worthwhile. We played a gig to 3 people once and probably contributed to the pub stopping live music sadly. Even if people really love music they still need to make it economically viable. I have to say that there is a place we played for years 'for the love of it' but the landlord of the pub must have made quite a bit of money over the time but could never afford to pay for a band... which rankles a bit.

Steve Knightley played in our village recently and good for him that he can command the fee he charges. The place was full and made a lot of money for charity. I'm guessing on the way up he might have done the odd freebie to get noticed and in his case it has paid off.

I've had lots of evenings though where I have had the fun of sharing some songs and music with people which wouldn't particularly have been enhanced by getting a few quid for it - the fun was enough.