Folks are mad that a company makes money following the basic principles of capitalism.
Folks are mad that the same company is spending some of that money to protect both your rights and their own.
Folks are also mad that the same company that they're not forced to buy from is now taking a stand to protect your rights and their own.
Folks are mad that this company is doing so publicly in a way that will be sure to get some amount of press coverage and could garner the very sort of attention most needed to protect your rights and their own.
What sort of behavior needs boycotting now?
The starving (in this case gun owners) need friends with food (in this case sympathetic and supportive vocal public backers). Keep it up folks. Our 2A rights will keep slipping away before our eyes. In-fighting is the surest tool of our opposition.
In the land of the blind, the one-eyed man is king. -T.W.