I agree, the park can't accommodate to every single persons needs. People think they deserve special treatment, I understand that it probably was embarrassing for her. But in all honesty what does she expect? They pack the rides, with all the people, they see hundreds of people everyday that want special treatment. Also, if you bought season park passes you should know about the rides and which ones you can and can't have your own personal space on. If you don't like it, lose weight. Simple as that.
ALSO, I'm sure they weren't rude to her and told her to get off if she didn't like it. They wanted to make things right... but she just HAD to file a "discrimination complaint". That's a damn democrat for you.