I often use the term nerd even when "geek" is probably the more precise one, because I think geeks have to some degree retaken the term, while nerd includes the implicit insult which is required. If geeks run the world and geekstuff is cool, then the term no longer has much derision attached to it.
But, anyway, dudes who show up to fast food restaurants open carrying automatic weapons (yes, gun nerds, they probably weren't technically automatic weapons or maybe they were but I don't care because big scary gun that can fire multiple rounds quickly is automatic enough for me, so stop being such a damn nerd about it) are nerds. They're mad that their little hobby of showing their external death penises to the world doesn't get quite the respect that it deserves, or more importantly they're mad that they don't get quite the respect that they of course deserve and are confused that their giant external death penis waving isn't giving them that respect. They want more adulation than they're getting, and don't get that their hilariously deadly hobby occasionally inspires a few eye rolls. Also, too, fear, but so what, nerd, any of us can buy an external death penis, because USA. It doesn't make you special.
I don't expect everyone to appreciate my hobbies, and certainly don't expect anyone to think they make me supercool or worthy of adulation. And walking into a Wal-Mart and plunking down a bunch of cash for giant external death penis isn't especially impressive, really. Waving them around is silly. Nerds.