Does anyone know when the stroller situation got so out of hand?
My son is 37 and my daughter is 38, so it's been a LONG time since I pushed a stroller. When we took our kids to WDW I don't remember there being such a stroller problem. The first trip we took the kids was when my daughter was 5 and my son was 4. They were both too big for strollers then. I do remember seeing SOME strollers here and there, but not walls of them. Looking back at old pictures, I can't pinpoint where the stroller epidemic started but I think around 1995 or so I start seeing big sections of strollers in the background of things. Before that, I don't see all that many strollers.
Do you think it's because parents are keeping the kids in strollers longer? I see kids who look like they are 6 or 7 being wheeled around in strollers. Maybe the kids are just old-looking, but they are too big to be in strollers in my opinion. I also notice that parents today treat the strollers like luggage on wheels and have them stuffed with all kinds of stuff. Not sure if this is really needed in the parks.
I really like how the Dumbo Circus Area addressed the stroller issue. I also like that they are doing something in the Tangled Potties area to address the stroller issue.
The park is SO MUCH more magical if the strollers could be hidden away somewhere.
Here's my take on your question.
Our first trip was in the summer of 1977. Things where a lot quieter in those days. There was only one park, and two hotels on site. So, you just didn't have the volume of people that you do now. That's why there is a need for things like FastPass (to organize queues better), RFID (to expedite entrance), and even special "pay for" parade / show viewing spots (just did the Fantasmic package on last trip.)
The volume you see on an average day now would have been a peak(ish) day years ago.
So its not that there didn't used to be strollers, its that there are just so many more people that they are far more noticeable.
ALSO, to address your "are parents keeping their kids in strollers longer" question.
We went with our son last month, he was 4.75 yrs old. He NEVER uses a stroller at home, hasn't for a year and a half.
BUT
We brought it and had him use it because of the massive amount of walking we did. He just isn't used to walking 10+ miles in a day (nor should he be a 4.75 yrs old.)
Again, to go back to the olden days. When we where kids, we would decide to do ONE LAND for a day, maybe half of another land in the evening.
NOW we decide to do ONE PARK for a day and maybe part of another PARK in the evening.
When we go we do so, so much more walking and cover so much more area because there is so much more to do. On our second trip EPCOT had just opened and that expanded things a bit, but back then they had Omnibuses taking you around World Showcase because of the distance, now you hoof it.
SO
The stroller issue is due to volume of guests and the inclination of guests to let their kids ride because of the vast ground they cover in an average day.