I have read a number of posts on the issue of the letter from the Starbucks CEO. The main thrust of most of them is, “don’t be a ass”. Concealed carry your piece and be polite. I fully agree with that.
However, I think it gives too much away to make the blanket statement that Starbucks (or any other business) is private property. Once a business opens the door to public traffic, it is different than a private home. If a business says it won’t serve minorities, or gays, or anyone wearing a symbol of a particular religion, we have rightly come to see that as discrimination and have said that Constitutional rights trump the beliefs and privileges of the business owner. Well, the 2nd Amendment is part of the Constitution as well, and my exercise of rights includes the right to bear arms. The same document that protects others protects me.
Saying that a business may limit my access because I am exercising a Constitutional right is no different than saying a business can tell blacks to come to the back door while whites are served at the counter.