If you do not want to buy from the companies of local corrupt businessmen, that is a good moral choice as a consumer. In fact,it should be a basic principle in the way we spend our money; that we do not use it to increase the power of evil people. That said, I do not see this as a revolutionary priority.
Liberation will not come through bankrupting anyone, even though it may be emotionally satisfying; the impact on the system of global domination will be insignificant. Organizing a boycott whose objective is simply to destroy the personal wealth and position of an individual will not achieve anything in terms of policy, but it will drain the energy and resources of the people participating in it, while diverting their attention from more important enemies.