It actually looks like they were pretty reasonable here, as they offered money for the company to help rebrand even though they were clearly infringing on their copyright. Of course, there are three sides to every story.
Trademark, not copyright. Legally they are very different.
Clearly infringing on what? Do they have "leggo my eggo" itself trademarked? And is it really reasonable to think there's consumer confusion between a waffle and an egg roll that isn't using the word "eggo"?
I would say they're clearly not infringing on any plain "eggo" trademark.
How is a 15M lawsuit ever reasonable in a case like this?