They profit through the 30% cut on any software sale. The cost equation for online subscriptions is as follows:

“Can we get away with it?” “Yes we can” The end.

Ok PC they can’t get away with it because there’s no single company controlling everything, so you either get every single company asking for an online subscription, you find other ways to monetize. Closest so far is Microsoft’s game subscription thingy and others like that. It’s not the same, but I’m pretty sure that’s the only way they’ve managed to convince enough people to pay a subscription on PC for now.