What do you do when you are personally of the opinion that some business with which you do business is corrupt?
I tend to seek out a less corrupt business.
Here in Miami, just yesterday, several gas stations with no nearby competition hiked their gasoline prices up to a dollar a gallon, based on the supposed limit in supply caused by Hurricane Ike, which could not have possibly affected the cost of the gas in their tanks so soon. I take note of such places and never buy from them.
I would not buy less than I needed to punish them, that is punishing myself.
The key to limiting corruption is better supervision, not restricting funding.