You know, I see this one pop up frequently on threads and "top Disney annoyances" polls (along with the related stroller and "kiddifying" of Disney comments) and I get a hearty chuckle everytime I see it. Why? Because they're typically made by people who either don't have kids or are older parents who don't remember what it was like to have small children.
Do you have any idea why a lot of parents result to putting their kids on their shoulders? Because adults who crowd front rows and prime viewing locations of said shows (parades, fireworks, etc) and then treat any attempts by the shorter set to get in front of them as incursions on their national borders. Honestly, it has been my experience that the only people that let kids in front of them so they can see are other people with kids.
A sampling of actual comments my son and daughter have been subjected to in previous years while politely asking for some room to squeeze in:
"Don't you touch me."
"I don't think so."
"If you wanted to see the parade, you should have gotten here sooner."
"..." This guy I thought was especially rude because he spent the entire parade on his smart phone and just stared at my son's futile attempts to get by him with a smirk.
So, up on our shoulders they went.
Sure, anyone who does this should be aware of their surroundings and do their best to not negatively impact other's viewing experiences, I just find it ironic you (and others) are railing against parents for blocking the views of people behind them but not those in front that are blocking kid's views. As long as Disney doesn't provide dedicated "kids only" sections for all shows and allows inconsiderate adults to hog all frontal viewing spots, I reject calls to prevent kids from being able to enjoy the parks like everyone else.
I think it's clear most have us have experienced people in ECV'S that didn't have full control. I for one remember helping someone in one who got stuck on some steps after accidentally throwing theirs into reverse.
That being said, your bolded statement is a perspective sorely lacking in these discussions. It's easy to criticize ECV drivers and call for their banning, but few people have experienced what it's like for someone in one.
Sadly, my eyes were opened to how the disabled are treated by the general public a couple years ago. My wife and I were celebrating our 10th Anniversary with a day at the MK (since we had our honeymoon there), but because she was 2 weeks away from delivering our daughter, I pushed her around in a wheelchair.
Attitudes and behavior towards her ranged from ignorance and obliviousness to righteous indignation. The most common thing I noticed was people walking around then back in front of us as if we were slowing everything down.
2 incidents in particular, however, stick out in my mind. I was pushing her along when a guy just kept backing up, taking a picture. He backed right into her, knocking her drink out of her hand. He yelled at us, though, for running into him.
Later, as we were leaving, we decided to hit up the Emporium on our way out. I was pushing her towards one of the curb ramps that leads into the store when I noticed a guy walking towards the same ramp at the same pace and at roughly a 45* angle from us. We looked at each other, and I figured he'd just let us use the ramp and he'd step up on the curb. Instead, he jogged to beat us to the ramp. He turned around as if to say, "Yeah, I just beat you."
All these topics go to show is we all need to do a better job of being aware of our surroundings and more considerate of others, though some have far more work to do than others.