Many states are currently working to pass, or have passed, new restrictions on the kinds of firearms and magazines that citizens can own. In particular, New York has enacted the most draconian restrictions in the country. In response to this, quite a list of firearms companies is declining to sell firearms to the governments and police departments of states, like New York, unless those same items can be purchased by regular citizens of that state, too.
However, if you peruse that list you won't see the largest names in the industry, like Glock, Smith and Wesson, Remington, Colt, Sig Sauer and Springfield Armory. These companies are the primary suppliers of firearms to government and law enforcement, so they'd have the most to lose by refusing to sell, but they'd also be the most effective at forcing the states to treat all its citizens equally.
Some folks have tried to excuse this behavior by saying that they're all publically traded companies, so they have a financial duty to the shareholders to maximize profit; refusing to sell to a large and profitable market segment would open those companies up to lawsuits. While this may be true—certainly in modern America you can sue anyone for just about anything—it does seem to ignore both history and current parallels.
Anyone remember the anti-aparthied boycotts and sanctions of South Africa in the 80's? Pepsi, along with a number of other companies, sold their assets and pulled out of South Africa in response to public pressure. Were any of those companies ever sued by their shareholders, and if so, did it ever amount to anything? (Not to my knowledge, and no, respectively.) Furthermore, currently there are groups who claim that Israel has enacted a form of apartheid and they are advocating for a boycott of Israeli products. I couldn't find any companies claiming they'd love to boycott Israeli suppliers, but they couldn't due to their fiduciary duty to their shareholders.
So, while the duty to shareholders may be a convenient excuse, it's one that doesn't stand up to scrutiny.
Important note: I'm not suggesting that gun owners "get medieval" on the companies that aren't participating in the New York boycott. I'm just pointing out that the meme running around about the financial duty to shareholders doesn't really hold any water.