A business should have the right to say what I can and can not bring on their property. I can tell you not to bring something on my private property, why can't they?
Becasue the 2 are not even remotely close to the same thing. Go buy a building in your town in the business district, dont get a business licesne or perform any business, and just live in it as your new home, and let me know what the govt says about it. Same with your current home. Open an assembly line with employess in your basement, or open your front door ans start selling keychains or something, and again, let me know what the govt does.In both cases, when you get you fine, eviction notice, court date, whatever, tell the judge about you property rights and see if you win. A business, even one owned by a single individual, is not the same as his home in MANY ways, so the rules on what you, or others, can and cant do in each are different, and in the case of a business, the rules are set by the govt, since they are ALLOWING you to have/be a business. I havent seen anything in the bill of rights about a right to be a corporation, or even to run a business. those are manufactured constructs/entities created by the govt., not natural/God given/constitutional individual rights. A business vs. a home is just 2 very diffewrent things, and thus, so are the rules for them.
Also, as has been brought up, the real issue isnt about being able to get into your car to acces your gun for SD while at work, it's more about having it available every second you chooses to do so on your way TO and FROM work, and wherever you may go/stop during that time, when you are off company property and off company time. Being able to get to and use it in the event of a workplace shooting in the building you are in is VERY slim to none. It's all the rest of the time this is about.
I fully support EVERONE'S right to set whatever rules they want as a condition of entering or being on/in your privately owned, non-business licensed home or land. You want to put up a sign that says "No women or Jews", or "Everyone must be nude-no clothing allowed" and enforce it, have a ball, it's disgusting, but it's your right on your private, non-business property. Do the same at the 7-11 or Kinko's, or whatever busines you own, and you're outta luck, prepare to get succeesfully, and very rightfully, sued and screwed, in the least.
My .02 cents, and as always, YMMV.