The original intent was to "give something back" etc, but I do not want to undermine musicians who make a living.

That's my feelings too. In addition, it sort of depends on who's asking. If it's because we contain mums and/or dads and we play at our local school concert, that's great. My missus works as a volunteer (as everyone else there does) for a organisation for people with dementia. Their funds are extremely limited and I don't mind doing stuff for them. But a care home is a business, just like a pub or a club is a business. Us playing in care homes improves their business. If you work for a business and help to improve that business by so doing, you should expect to be paid. It's all time away from home and instruments have to be bought, replaced, restrung, etc., and petrol paid for. The undermining point is also very important. Round here, a band which asks for a pretty reasonable fee for a gig is often confronted with the claim that the blokes who played here last week did it for nothing/a lot less than you're asking. One often scratches one's head at the thought that a DJ on his own could rake in five or six hundred quid without demur.