I don't remember any of my family ever "losing it" in Disney. Got a bit grumpy at times, but never "losing it." However, we've seen many full-blown arguments and fights that other guests have participated in. My family usually all grin at one another and say, "Looks like they're having a Disney moment," in sugary-sweet voices. "A Disney moment" is our secret phrase for bratty kids, shouting matches, and basic bad behavior demonstrated in public.