It would be colossally ignorant and petty for the firearms and ammo manufacturers to put the lives of citizens and tax payers of these states at risk by refusing to sell them the tools necessary for the defense of self or others.
First, S&W, Ruger, Glock, Sig, Benelli, Olin, etc. etc. are in the business of selling firearms and ammunition. The state and municipalities of NY are customers engaged in buying those tools to protect their citizens. No one on either side is strengthened or weakened by those companies reducing their sales just to strike some petty political affect.
Also, no corporation should breech its fiduciary duty to it's shareholders, employees and/or private ownership through reducing its revenues by stopping sales of it's products on the basis of political grandstanding.
Finally, the fact that LEO in NY buy these magazines, rounds, weapons etc. is a signal that those tools are effective in the defense of self and others. So effective in fact that the state uses tax payer dollars to purchase them. Refusing to sell them to affect a political statement undercuts one of the strongest rationale's for keeping the weapons, magazines and ammo available to the public: they work so well, LE uses them. By refusing to sell them, the mfgrs undercut the very public rationale for the need for their products.