Sebastian (mostly) and I have been defending civil behavior toward those that disagree with us.
In contrast see how Brady Campaign people treat others when they ask to be left alone. Paul Helmke says Sorry, Starbucks: You Are In This Debate. That is being a jerk and doesn't further your cause any. Just quietly avoid them and you will be viewed far better than picketing their stores.
There is a reason the Brady Campaign is doing this--they don't have many options.
We have enough purchasing power that we can make a major impact on our friends and opponents. The Brady Campaign cannot. They are on a downward spiral into oblivion and they need a win soon in order to have relevancy. They invested a lot into this battle with Starbucks. They were very, very public with it and to have Starbucks tell them "please just leave us alone" is a huge blow to their egos and their status. It affects their influence with legislatures and it affects their income.
The best thing we can at this point is to quietly, unobtrusively, politely buy Starbucks products. Let the Brady Campaign throw their tantrum. Nearly everyone is going to recognize them for what they are. They are jerks no different than those that would insist no blacks, Jews, or mixed race couples be served.