It's more nuanced than that. One should do business with people who are against the regime. If you stop doing business with them - those people will have to d

It's more nuanced than that. One should do business with people who are against the regime. If you stop doing business with them - those people will have to do anything to survive including being more dependent on regime's assistance, developing dependency and loosing even more of their free agency. This is also why sanctions are targeted - you need a carrot and a stick.