Usually yes, and I will acknowledge that skipping this step is showing laziness or incompetence, but I don't think children are already reasonable, especially when they're tired (this happened late in the evening) and already committed to throwing a tantrum. And in this case the whole situation might have been already stressful for the parents anyway, which doesn't help. Probably they should have talked about it more way before they entered the plane, and prepared the kid for what was going to happen. And maybe they did. But the situation then being what it is I think options can be very limited, and there probably wasn't much time to try reasoning with the kid