I think you've got it right there. A cursory search of Wikipedia shows parodies may fall under fair use, never mind the copyright notice: http://en.wikipedia.org/wiki/Parody#Copyright_issues
(In theory, the reason EULAs work is because when you run the program, you are copying it from disk to RAM. This is why they are believed to be very shaky, as copyright law does not specifically consider copying from disk to RAM inside a black box to be "copying".
The GPL is on firmer ground, because it covers copying for distribution to other people. That is a situation that copyright law is specific about.)
This is exactly why people like me get confused about such things. From the little reading I've done I tend toward the "copyrights sound like the solution, and everything else is a twisted interpretation of that" point of view, but I'm only well read enough to know that I'm not well read enough to have an actual opinion.