It's not the same concept, at all.

Building your company around the core business of LinkedIn/Facebook/etc is dumb, because you are nothing more than a complement to their core mission. Best case, you become a commodity and achieve modest success, but the oxygen gets cut off at any time.. If you're very successful, you become a feature of the mother product.

When you're Apple buying memory from Samsung, that's different. Samsung's output is memory chips... that's the business. If nobody buys memory chips, they lose money.