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.