"If they can dangle that carrot in front of you and get you to give 110% at your current pay scale for 1-2 more years then why the hell wouldn't they do it?"
Cause that's a shitty thing to do. And, as shown, it leads to people leaving.
Yes, (most) people care that it's a shitty thing to do, but again companies like this do not. Their goal is to grind as much productivity out of you for as cheap as possible. It sounds fatalistic but it's just how it is. Romanticizing things just leads to heartbreak.
EDIT: Note I said "companies like this". There are clearly companies that are run at the top by compassionate, non-shitty people and those values filter down through the org. However, as companies get larger and especially once they are beholden to investors and ESPECIALLY when they are beholden to public investors that seems to die a gradual death.
Cause that's a shitty thing to do. And, as shown, it leads to people leaving.