Of course it's not a real thing, but if someone who had better organizational skills and charisma than me were to get one together, I'd love to participate. Imagine hundreds of thousands of AR15-toting, responsible gun owners marching on Washington to demonstrate our presence. What would that tell the other side? All those "assault guns" and not a single shot fired.
Of course that idea would be playing with fire because I'd imagine some anti would obtain a rifle and open fire from the middle of the crowd to advance their cause.
Then of course I'd imagine most gun owners have JOBS and would find it difficult to participate.