Do you honestly believe they are going to abide by gpl restrictions? Really?
No, but saying just because it is open source they can do what they please with it, makes no sense.
Compare it with this situation. Say there's a student who is looking for stuff to put in her essay. She doesn't mind cheating. You are saying that because there's a book in the library that is on the topic she has to write an essay about, she can just copy it all into the essay and be done with it. To be clear your argument is: it's in the library, therefore, she is allowed to copy it.
I say, no, she would have to use APA referencing and quote the text and say where it came from.
You say, no, because she's a cheat, the book being in the library means she can copy it.
This makes no sense. The fact that the book is in the library has no bearing on whether she will copy it. She could equally well buy a copy from a bookshop and then copy it, buy an ebook online and then copy it, or break into the author's house and copy it off his laptop, etc.
Your argument is like saying My dog is black, therefore, his favourite food is baked beans. One has absolutely zero to do with the other.
Being open source ONLY means that you can copy it if you follow the license, just like a book being in the library ONLY means you can borrow it and take it out of the library for free. Being open source has nothing to do with whether you can use the code and violate the license, and being in the library has nothing to do with whether you can copy the content without using proper referencing.