So they're not going to make the same mistake again. They'll sell more copies if they release both versions separately. As you said, they want to maximise profits, obviously.
It's their game, they can sell it whenever, however and for how much they want. It's up to you and everyone else to decide if you believe their product is worth it.
Just as an example; I'd like to play the Remastered COD4 multiplayer, but I'm not paying €100 to do it. Not because I have a problem with Activision, or I don't like how they're maximising profits, but because I don't think it's worth it. Simple.
If your so sure they're going to release a PC version, just wait till that comes out and buy it then.