To protect consumers and strengthen distributor independence many states began enacting laws in the 1970s known as beer franchise laws. These regulations ensured, among other things, that distribution agreements between brewers and distributors could not be unfairly terminated. Beer distributor independence is essential to a free market beer distribution system.
If brewers could unfairly terminate a beer distribution agreement it would likely coerce the beer distributor into taking any number of undesirable actions, such as violating liquor laws, not carrying competing brands or only serving select, favored retail accounts. Rather than the craft beer explosion we are experiencing today we would likely see a far more restricted and far less diverse beer market, ruled by the largest and most powerful brewers.