Is Disney making more from EMH being a driver for hotel room occupancy, you betcha.
Are they though? You need a LOT more cast members to open MOST of the park early or later.
And really .. how many people (besides the "go every year" fans on these boards) really make the onsite/offsite decision based on EMH? For me (who was well aware of its existence) it was a great bonus I could take advantage of one of the days but it was nowhere in my decision making process of whether I was going to stay onsite or not.
I feel offering people a 4th FP for staying onsite would be a MUCH more desirable perk and fill up the hotels more. (if the system could handle that capacity, which it may not be able to).
I can easily see Disney eliminating EMH if these EMM are popular (why give away for free what you can get people to pay for). But I think the two can exist together since they offer different things.
The problem with a boycott of special events ... they are limited so much there will always be people to pay for them. It would be like trying to boycott an expensive car.
We've created the problem ourselves by making WDW so popular.
WDW is such a popular place it gets more and more crowded. Thus there is more demand for things that help eliminate the crowds:
FP+ - to skip 3 lines on a busy day without having to run to a ticket machine. What an awesome perk.
EMM - Being able to have the park to "myself" and ride some of the most popular rides MULTIPLE times?
Dessert Parties - Being able to have a seat to yourself (not packed like sardines) to a night show.
Dinner packages - Being able to get reserved seating to a night show with having to wait in line or worry about seating.
Disney is just filling demand (and charging for it, because it is not free to do those things).