The thing that I actually found the rudest during the Princess Half was the guy (that wasn't running it) that proposed to his Princess (that was running it) right in front of the castle. We came to a complete standstill, just waiting to move again. Sweet for the couple, very inconsiderate of the thousands of runners waiting.
I was disappointed in not actually being able to run through the castle. Shuffling through the castle in a mob was not what I was expecting at all. I also didn't get to run across the finish thanks to large groups of people walking across all arm in arm.
When I think of my internet friend that had the sweeper bus pull out right in front of her at mile 8, all I can think is that Proposal Guy and the time she lost standing there cost her finishing and getting her coast to coast medal. She got swept by literally seconds, and I know I lost more than mere seconds there. My mile through the Magic Kingdom was 5 mins slower than all the miles leading up to it, and I only stopped for 1-2 mins for a pic in front of the castle.