This entire thread amazes me. What kind of stroller anyone brings in to the park or what age the children are is really nobody else's business but your own. Yes, I've been hit by strollers before. I've also been hit by ECVs, and my 2 year old son was knocked down twice by members of South American tour groups at WDW. Does that mean we shouldn't let South Americans in to the parks? Or people in ECVs? Of course not!
There are rude, inconsiderate people everywhere. You can't usually do anything about them...just deal with it. I don't understand how you can judge people for bringing a double stroller that you think is too big. The Disney strollers are big and not comfortable for any child. I'd rather parents use a double stroller than have small, crying children being dragged through the park by tired parents. Nobody wants to carry their heavy toddler all the way back to their car or hotel and nobody wants to hear crying, screaming children because they have to walk because their parents wouldn't bring a stroller for them!
For the people who think that children over the age of 5 shouldn't be in a stroller, not every child is the same. When we go to WDW we usually stay 10 nights. My 7 year old doesn't have a stroller and walks everywhere. During our last trip we used a pedometer and we walked 45 miles over 9 days. My son was amazing, but he was exhausted by the end of the trip. On our last day at Epcot we rented him a stroller to use when he got tired. I guess some of you will just say we should have cut our trip short because our son was tired...absolutely ridiculous! What we do shouldn't concern anyone but us.
We're extremely considerate with our strollers. The only people we have ever run into decided to stop dead right in front of us to take pictures or to look at their map. They were completely oblivious to anyone around them. Still, I always say "excuse me" or "I'm sorry" whether it was my fault or not. Being considerate and good manners can go a long way.