He is acting very reasonably. HERE'S WHY: 1) Starbucks has previously had an entirely neutral stance on firearms. Having pro-gun rallies there is a blatant attempt to scare the antis. 2) It would have been smarter on the part of gun owners to ONLY open carry there if they normally open carry on a daily basis. We should have treated Starbucks for what it is, a gun-neutral business. The anti's could have tried to sensationalize it all they want, but we should have just ignored them by simply continuing to go about our daily routines, not by combating them.
Starbucks chose a gun-neutral stance to avoid any conflict, which was smart. And yet, rabid antis managed to get an exaggerated reaction out of some gun owners (carrying AR15s is obviously not a daily routine for virtually anyone), which caused conflict. If only we had ignored the antis, only one side of the argument would have been speaking, and I believe Starbucks would have seen that and ignored their unwarranted rambling too. Now Starbucks has taken another step to ensure that conflict is minimized.