Some commodities are more vulnerable to collective pressure than others; recognizing the distinctions in production among commodities is not hypocrisy. For example, boycotting chocolate is simpler than boycotting oil, and moral responsibility varies based on the circumstances that gave rise to that commodity and whether or not those circumstances can be addressed socially
When we boycott one thing but not another, morality as a signaling mechanism takes on a tactical character; similarly, when you're laying siege, you aim for the paths of least resistance before storming the keep. Building upon one victory after another, gaining confidence and cohesion as you go
You can't climb every wall simultaneously, so it's pointless and counterproductive to use that impossibility as an excuse to not do something, even individually, which is just the component cell of collective action