It's not a soundbite, it's quoting Tim Bray. If you don't like it, go ahead and call it a strategic partnership, or a mutually beneficial symbiosis, or whatever else floats your boat. Meanwhile, Apple is yanking the rug out from under people.
Given that I'm using this term in the middle of a debate where the subject being debated is Apple's draconian behaviour towards iOS developers, I think that if you want a different analogy, the onus is on you to find one that is a better fit, not on me to defend it.
The sharecropper analogy is so absolute it's useless. It makes for a lovely soundbite, though, I'm sure it's fun to repeat ad nauseam.