If BrammoBrian changed his, I believe that it should be legal. I don't think Craig would let anyone working for him to break the law... but, then, I don't know Craig.
It could also be a legal issue in some specific markets and they thought it would be easier to go with it than offer too many options in the first batch. They can tackle it on a second or third edition if sales are high enough.
In my opinion, Brian's mod looks good and if he is changing it, Brammo should be thinking on standard options for that tail. Unless, they made it on purpose to give people something to tinker with and get them more involved with the aftermarket community, increasing the general buzz around the brand.
Back lights, mirrors, and clip-ons are easy mods that any beginner can attempt without much risk and feel like they have an "unique" and more personalized motorcycle, so they have something to talk in forums like this one.
People don't buy motorcycles for utilitarian purposes only (at least not in the US). So, building a community based on easy mods would definitely work in Brammo's favor in the long run.