While it's not unheard of for something bad to happen in a shop or at a gun show, the odds are against it.
The odds are against fire and auto accidents, and violent crime, and lots of things. We still take steps to reduce those chances for ourselves, and for society when we are able. In the case of gun safety, WE ARE ABLE.
There are idiots everywhere and you'll just wear yourself down trying to correct them all.
Sure, there are idiots everywhere. We do NOT have to suffer idiocy at our gun ranges and gun stores. Stand up and say something. The life you save may be your own. But it may be your friend's, your neighbor's, that of the proprietor of your favorite LGS. And, the life you save may be the one that
doesn't make it into your local papers as another sensational gun accident, another tragic death "due to guns."
I may be in the minority on this, but you can seldom go wrong by minding your own business. If it bothers you that much, just try to stay 'up range' from the offending party.
This is not a case where "minding your own business" is the appropriate answer. In thousands of other instances, I'm totally of that mind. BUT, when it comes to firearm safety, you CANNOT go wrong by standing up for best gun handling practices.
So often in society it only takes one person with just an once more moral courage than everyone else in the room to totally change the current of how things are going, and how things are done. One voice that says, "
Hey, that's not cool. Please follow Cooper's Rules: Treat every gun as if it was loaded and NEVER point one at anything you aren't ready to destroy!" can be the simple prompt that clerk, and all the other clerks, and the other customers needed to hear to find their own voice and swing into line.
They DO know better, and the repeated laxity they're exposed to can wear them down. They think the whole world is full of ignorant slackers who don't know and refuse to care about safety. A guy (or gal) can only take so much before his/her own determination to uphold safety drifts off the straight and narrow. ONE customer willing to step up and say what MUST be said can be enough to put the spark back into that clerk and, as oregoneng (and others) point out, WE are the teachers who will make the biggest impressions on new shooters and our fellow gunnies. We, their peers, the average joes who they discover WILL NOT stand for bull(crap) gun handling, and WILL say something (politely) to correct it.
Be the good you want to see in the world. Just in this one thing, if none others.