So right, Michael.

And, sad to say, my experience is that in general the ones who can/will offer the least - both in terms of money and in terms of schedule flexibility - are the ones who take a booking the least seriously.   They are the most likely, when a new activity director or manager comes on board, to just cancel or disregard all the bookings previously made (sometimes without bothering to notify people of the cancellations).   
It seems to be an example of your perceived value being a function of how high or low your price is.
It's very frustrating, when I try to bend to accommodate clients' budgtary boundaries, to find that flexibility 'rewarded' by my services being devalued.

Still, doing music for the frail elderly or cognitively-impaired people can be very rewarding in and of itself.   If I didn't need the income, I'd be inclined to do a lot of this music gratis.
Part of me would say don't do it, because you'd be offering unfair competition for other musicians who do need the income. But I do all sorts of jams and sing-alongs and open mics (not to mention my church choir) without pay, so I can understand those who do provide music to various places as volunteers.