I'vee been on both sides of the stroller issue - both run over, and repeatedly cut off by non-stroller people. It is surprising how many people will cut right in front of a stroller! At junctions, we should all use the zipper method!
People who block pathways (and otherwise hog space). They get their group to an important juncture spot, and then stop, while they debate their next move. Also, groups who block the entire path and walk slowly. Americans seem to have a huge problem with this in general - I don't understand, WHY CAN'T PEOPLE REMEMBER TO STAY TO THE RIGHT!?!?!?
While not vegetarian, I wish more quick service places had more veggie options too. At a number of quick service places, the veggie options are iceberg lettuce/salad or french fries. But this is true of too many American restaurants in general. I wish they served a simple side of steamed broccoli or snap peas
I wish there was something else to drink (besides water) in restaurants that wasn't full of sugar/corn syrup/caffeine/artificial sweeteners...but I suppose that is too much to ask....even of a magical place like Disney! (At least more places have some options besides soda nowadays.)