Proxy war? I can use my wallet, my voice, and my labor power as I please including strikes and boycotts. Isn't that how the "free market" is supposed to work?
This is the 2nd time in 24 hrs that someone has made your argument, where is it coming from?
I don't think it's silly. I don't boycott companies -- that is, I don't stop doing business with companies in an attempt at getting them to change their behavior.
However, there are companies that engage in activities that I find objectionable enough that I simply don't want to help fund them. So I don't buy from those companies. Nothing silly about it.
Why? Both corporations and governments are, in theory, supposed to take actions that maximise benefit to their stakeholders. If those stakeholders decide in the majority that morality is a way in which they seek to derive value from either a corporation or a government then those institutions are presumably bound to deliver on those requirements or to be subsequently punished by the majority or their stakeholders. The fact that shareholders (and customers) seem to be more inclined to be demanding moral behaviours from companies, even though they are also (presumably) citizens, is possibly an indication of the fact companies are more responsive in this regard.
This way just creates chaos and rarely results in any long-term change.
And the government changes all the time. It's called voting, and interacting with your representatives. If you have time to be outraged at corporations then you certainly have time to be involved with politics to create change.