1. When it does happen in a theater. They typically refund you back in full, give you free passes for the next time, and typically concessions if you care. Last time it happened to me, got my money back, two free tickets, and all the Ice cream I could eat(Power went out, so they said since it's melting, take everything)
2. A movie is not even close to a comparison as a plane. A plane is a must be place, typically with family, emergencies, or money(hotels) waiting on the other side. We knocked you off so you can't go on your vacation? Fuck that shit. If it's their fault, they should have to reimburse the ticket in full, comp your next flight, and pay for everything you missed. Then give compensation on top of it.
Because if it is was an actual fucking business with competition rather than a Cartel. This is what would happen. People would tell them to fuck off.