While I don't doubt takedowns are swift, unquestioned/undisputed, and can have a chilling effect (intentional or not)...
it's not entirely cut-and-dry. See http://www.inta.org/INTABulletin/Pages/NotAllIsFair(Use)inTrademarksandCopyright... and http://www.betalaw.info/can-lose-trademark-rights-dont-sue-infringers/
Particularly, simply using a name is not necessarily infringement (people aren't going to assume association of Nutella just because it's the centerpiece of a recipe, and if anything it will boost sales of the trademark holder) and intellectual property doesn't need to be protected like the last thin-shelled egg of an endangered species that's largely undocumented.
I'm sure if fan games are ever attempted to be used as a defense to claim abandoned intellectual property that defense would be stricken down. Certainly if said fan game is gratis (and non-commercial to a certain degree, especially if the difference of revenue vs profit is taken into account), non-competing, not intended to cause confusion, and not causing significant damage to the brand. And heck, if EA match all of that, then more power to them (considering their track record, I doubt they can accomplish any of that).