I think the thing is if you see it as "I choose to spend my money on X, you could do the same" you kinda miss out on the root issue.
The feelings people have is taking something that used to be available to those staying onsite (EMH) and while they removed that barrier of having to be onsite with doing DAH they did it at a hefty cost. I remember when DAH first started it was not well attended nor as received because it was so new and they didn't do much announcing before they started it.
Now as more and more people attend there's more urge to have more dates, stretching out throughout the year what once used to be limited to a small portion of the year. Less opportunities for EMH to begin with. Call it a vicious cycle if you will. The more people seek out the potentially less crowded events at nighttime the more limitations will be placed on the average park goer.
The same can be said for the parties. It keeps getting earlier and earlier. This can and does negatively impact people. I don't care what you personally choose to spend your money on but if collectively enough people do xyz it pushes the acceptance there which adds fuel to the fire. I've always been about pay whatever you want when it's not so overt (like the MK tents) or impedes on your average park guest and the changes done in recent times with the parties and DAH do impact your average park goer.
The time slots of DAH means park closing time can be earlier too. Park hours used to be longer for just the average park goer though it's been great that AK's time was extended past 5 or 6pm like the olden days was . But if DAH starts at 10pm there's no opportunity to have park hours be later than that. And it may in the future start earlier than 10pm if demand for that extends. MK parties have already started the 6pm close vs 7pm close.
It's not really about free perks TBH because some of the ramifications of DAH affects your average park goer. Though yes park hours were never guaranteed