Because the EFF's 'stupid patent of the month' section was started pretty much in direct response to Apple using it's rounded-corner patent in its litigation with Samsung.
IMHO, the issue is that Corel's and Samsung's products were clearly and intentionally designed to imitate other successful products in order to mislead consumers. There are different opinions on whether this should be acceptable or not (obviously, the corporation that just had their flagship product ripped off thinks it completely unacceptable). Trade dress and seemingly stupid patents are just ways for corporations to fight this in court.
I'm sure we will will have a flood of well upvoted posts if apple tries to enforce that patent.
Didn't that already happen with the samsung lawsuit?