When they really need to. But they'll fight it hard! Apple's business model is to lock everything down -- very closed indeed. This does not align with the goals of bitcoin, at least, how I perceive them.
tl;dr Apple = closed. BTC = open.
I had no idea that Apple will going to accept bitcoin. But I heard it before in the news here in crypto and bitcoin world, so for me its just an hearsay or rumors. Then, if ever they would accept it, I don't see any wrong with that matters. Although, Apple has a capability to make their own system that has a similarity of Bitcoin concepts where most of the altcoins did this things actually.