2 primary reasons:
a) I play in church - for me this is an integral part of my worship and is primarily for me. This is time with my God doing something I love using a gift He gave me in an art form He created. What could be better? The fact that people in the congregation (hopefully) benefit is actually of secondary, though NOT diminished, importance.

b) Other venues/groups:
This includes a couple of big bands (one is a student band the other primarily a rehearsal band though we are open for gigs), a couple of "show bands", and orchestra appearances for a couple of musical societies. I enjoy working with the other musicians to create a harmonious whole and I like to see and hear people enjoying themselves. When I am part of creating the enjoyment it's a real buzz. I certainly don't do it for the money; aside from a small token payment from one of the musical societies for which I play in the orchestra, all the playing I do is gratis. Not to say I wouldn't like to make a buck at it, but the last time I made a business out of something I loved (IT/computers) I eventually came to hate it. Perhaps this is part of: "It's more blessed to give than to receive"...

Interestingly, while I don't actually seek out recognition, when it comes it is always welcome and most pleasant. Especially when it comes from other musicians, most especially good ones. Perhaps my current greatest moment of this nature was playing the 'bone part for "Pirates of Penzance" when it was put on by Wyong Musical Theatre Company in May (?) of 2009. Apparently the society's members hadn't heard a reasonable (dare I say decent) trombone for a long time - not even sure they'd had one available - and the comments were wonderful. Took ages for my head to shrink enough to get through normal size doors again

--=-- My credo: If it's worth doing, it's worth overdoing - just ask my missus, she'll tell ya laugh --=--
You're only paranoid if you're wrong!