The government should not decide what services and products businesses can offer and what markets they can enter. These decisions should be left to producers and consumers. Under laissez-faire, there would be no buying of favors from politicians because politicians would not have any favors to offer.
All these laws would be impossible under capitalism, since each one of them is a violation of individual rights: preventing a group of businessmen to enter a market violates their right to liberty; taxing one business more then another violates the principle of equal treatment under government; subsidizing one business–with the tax money taken from the other–is a violation of the second’s right to property, etc.
Under capitalism, the only laws that a politician may pass are those that equally protect the rights of all its citizens, i.e., without violating the rights of any of them.