See, again - this is only true for parts of the year where MK is actually open past 9.
Many nights, the parks aren't open after the fireworks or they close 1/2 hour later.
If Disney actually kept their parks open late enough to enjoy in the evenings, I wouldn't give a fig about EMH. But there is a lot of the year when DHS closes at freaking 7, 8 at the latest if you are lucky. MK is the worst, though, because so much of that park is so much richer at night when it's all lit up - and during the times of the year they close up at 9, on alternate nights they close up at 7 for hard ticket events.
I think some folks only go during times when the parks are open later, so EMH goes until like 2 or 3AM or something - that simply doesn't happen for a decent chunk of the year. I have spent up to 32 days in one calendar year at WDW (on a half-dozen trips) and I have never been to MK at a night where it was scheduled to be open past 11, and even that was a rarity it's almost always been 9PM. Midnight is the latest I have been, and that's almost always been because of a hard ticket event. I honestly don't think I have been in the park after 11 without having to pay $60, even with EMH.