I'm not positive, but I'd guess the most prevelant modeling is humans (or something approxiamating a human). I've seen a fair bit of cars and guitars as well. Sounds like you may be exaggerating the amount of gun models floating around. Often it's the things we don't want to see that we notice the most. Besides, if all that was here were guns than the forum would have very limited use as it would service a niche population. Now if you're at the military meshes site, I'd expect a lot more firearms. If you still honestly feel that there are only guns here, then be a trend setter at post your own non-gun models.
Happy modeling.