[EpicEng]

>That's what they already do

No they don't. They overbook to maximize profits, yes. It sucks and is completely anti-consumer, yes. However, they do not simply send you packing. They re-book you. You also agree to it when you buy the ticket. Again, yes, it's buried in the contract and since every airline does it you really have no choice.

It's far from perfect/fair, but that has nothing to do with what I responded to. If "everything doesn't have to be a contract" then you have no legal recourse. Ever. Sales need to be contracts in the eyes of the law, but that doesn't mean everything is perfect.

[ptero]

Yes they do. At least in the US they will often cancel flights that end up mostly empty (they will certainly rebook those affected)