I know the feeling. In one of the bands I'm in, if the budget from any potential booking is too tight, they immediately offer themselves out as a four piece without me, with the keys player covering the bass.
Ultimately I have just decided f**k it, I'll turn up when I'm told and not worry about anything else. Kinda whizzed me off a couple of weeks ago when the guitarist refused to play because of water on the stage though, as I guarantee he'll have been paid the same as I was even though he just turned up and moaned, whilst I got on with it.