These are people stuck in strange places who are anxious and uncomfortable. Some of them are probably going to miss important things. Others have to worry about kids/pets/etc. That's not to say they shouldn't be patient (and certainly they shouldn't be taking their frustrations out on the airline staff), but you're demanding rationality from people in the exact sort of situation where it can be really, really difficult for someone to be entirely rational.
They're trying to do what they can (call customer service) and find themselves helpless - that's not a situation where they're going to reason through the economics of call center staffing.