What do you base that on? Seriously? What past behavior of Disney suggests that they have ever taken a perk that was free and decided to charge for it? They've cut some things back and they've reduced some services. But I can't think of a single thing that used to be free that they then charge for.
I take that back. Resort parking. I think there's a big difference between that and something as integral as Fast Passes.
But beyond that, I've got nothing. They've added parties, but they haven't gotten rid of nights -- and it's not like they were open until midnight every night, all the time. They've created viewing areas for fireworks, but they don't require everyone else to wear blinders. Even with DME -- they may end up discontinuing the service, but as far as I can see they haven't started offering the service for a fee. So what is creating this near certainty in your mind?
I can see being frustrated nothing has been announced and I can understand that people think the parks are rough right now. I just don't see why every single thing that happens has to be extrapolated to the worst possible answer with the worst possible motivations.