Neville,
Understand your point but a lot of the Angel flight pilots are PPLs and don't earn their wages flying anyway. Those who are working as CPLs give up their time (and duty hours) freely so raising the money issue is irrelevant. A lot of commercial operations would have secretarys who earn more than the pilots - these are the ones you should be upset with, not Angelflight.
Squawk,
In my experience if the weather looks particularly dodgy in advance then missions have been cancelled either early in the morning or the night before and either a commercial flight booked or in some cases the pilot has driven the patients themself. Also, the hospital knows that the patient is coming via Angelflight and so is able to rearrange things if there are holdups enroute.