Don't interpret me in the wrong way, but if these guys have wasted their time packaging a mod like EB and are sell it, I can only mean they deem the content is worthy of value, which is always good to know.

As for the legal issues, they are totally in the hands of CA, since they have all the legal rights. EB is a free content and doesn't work by itself: it always needs the original game. As such, in practice, these guys are actually pirating the original game and distributing EB along with it. So, the only entity that can legally persecute them is CA.