You lack the resource to grow your business, so you borrow someone else's and operate at their whim.
Contracts aside, the sharecropper's entire livelihood could be undermined on the whim of the landowner. Someone else has power over your ability to produce.
Not at all. Sharecroppers are typically protected by contract law; landlords can't just arbitrarily evict them in the middle of the growing season. By contrast Facebook can change their API or terms of service at any time. Facebook developers have no way to seek redress (except the court of public opinion).
You lack the resource to grow your business, so you borrow someone else's and operate at their whim.
Contracts aside, the sharecropper's entire livelihood could be undermined on the whim of the landowner. Someone else has power over your ability to produce.