So you'll sit there for an entire day and not get paid for it? Are you all nuts?
All of you should just get together and walk out when it's crappy or force the tight s*ds to at least pay you for your time.
I can sort of see where the company is coming from, but I think they are taking the p*ss somewhat. If the day is absolutely rubbish and there is no possibility of any of you flying, then go home, you are self-employed anyway.
The industry does NOT demand 'free' working, well at least not my little bit of it, you need to show some commitment, but this is taking the mickey.
Go and find somewhere that will treat you properly, there are plenty of jobs going at the moment.....
One last thing, does this company pay ridiculously high wages when you do fly? If so then you may just have to put up with it and quit moaning, but if they are stingy there as well, then just bail.