People have put skulls on everything since I can remember. Skulls are all the time found on cars, motorcycles, tattoos, clothing, candles are even fashioned to look like them. I've even seen a knife with a skull as a handle. But, the moment somebody makes a lower receiver that looks like one the guy who owns it must be a killer, people loose their damned minds hahaha. In the words of Eric Holder, "they have brainwashed people to think about guns in a vastly different way" That's propaganda at work for you. And I don't understand what the obsession with penises is either. If somebody has a nice car, must have a small penis, if somebody has a nice house, must have a small penis, if somebody has a rifle, must have a small penis wtf? Honestly, I'm not a fan of the skull receiver myself, but I don't think its wrong for somebody to have it either. I'm a huge fan of the AR platform. And the 2nd amendment says you have a right to possess a firearm if you so choose. But it doesn't provide you with one. And it is most certainly in place to combat a tyrannical government.
Islam has killed millions in the last decade, lets focus all attention on Christianity!