As a parent of five children, I can attest to the fact that people have often given us strange looks, like we're part of some cult because we had more than the statistical average of 2.5 children. I have seen the looks from people in restaurants or at church (!) when we bring our large family in. I could not even begin to count the number of "you know what causes that, right?" jokes that people have made, thinking that they are so clever and the first ones to ever make that joke.
You know the one place I have literally never gotten that look or that attitude? Walt Disney World. Not once have we been made to feel like we are some weird crazy cultists when we bring our five children into a hotel or a ride or a restaurant. People have been nothing but accepting and pleasant to us. And that really means something to my wife and I, and it's one of the many reasons that we love WDW so much.
Given that, I cannot imagine not extending the same acceptance and pleasantness to anyone else. If you are a childless millennial coming to WDW, more power to you. I hope you enjoy it just as much as everyone else. And even with five children in tow, sometimes getting irritated and impatient and even having the occasional meltdown, it would never even cross my mind to be upset, let alone take to social media with a rant, because someone who is childless got a pretzel ahead of my children.