I have been playing for my church for over 3 years now and the musicians have always been payed for their services. In fact we all just received raises for 2008 as well as a year end bonus for 2007 (first time thats happened). Playing is my way of praising but it takes a lot of effort and time as a musician to play well and that shows every Sunday. 2 or 3 times a year our MD (keyboardist) is out for vacation or illnes and if we don't get a replacement on keys (we) the musicians more than likely wont play. The choir /praise team still sings accapella but the energy of that service sinks like a stone proving how vital our "music" ministry really is. So, why not accept payment? However, I WILL start giving back 10% as an offering.
I see no problems with what I am doing.