Good times! Could never do this these days in Silicon Valley though :(
If you want to go down to the range after-work, by all means do so, but the way you Americans trivialise a toy good for nothing but war in many cases is really fascinating.
Firearms are most definitely not toys. A bring your gun to work day is a way for coworkers to bond outside of work as well as a great learning experience for the ones without much knowledge on how to safely and responsibly handle a firearm. It’s also a lot of fun shooting targets.
Ever heard of hunters? A LOT of people hunt. Also, until relatively recently it was common for american kids to bring guns to schools, and leave them in their car until after school so they could go hunting, etc. Instead of addressing things like mental health issues, it's easier to demonize guns because the politicians don't actually have to do anything other than introduce token legislation.
It's a right written in the constitution, and only referring to guns as "weapons of war" is political rhetoric. And hunting is not the only reason to own a gun- that's also political rhetoric.
It would be an amazing coincidence if none of your coworkers were interested in guns. Around 30% of Californians have at least one gun in their home. Naively extrapolating: that means if you have 15 coworkers, there is a 99.5% chance that at least one of them owns a gun. Even if only 10% of bay area techies have guns, the odds that at least one of your coworkers has a gun is still over 80%.
When my hobby became publicly known at work, I suddenly discovered I had quite a few coworkers who liked guns. They were quiet about it at work because they were afraid (rightfully) of hurting their careers.