I managed to make it to a couple of brewfests near here this month and was very disappointed by the overall quality of the beers. I was amazed at the paucity of good beers, and the number of bad beers, and I don't just mean the weird "blueberry- mint julip-frappe breakfast saison" crap, I mean beers that had so many quality flaws that even my burned out taste buds couldn't help but notice. Granted both fests took place far from any population center, but I had the same experience last year at the Knoxville Brewfest.
I think breweries get away with selling crap beer because so few people can really tell the difference between well made beer and garbage, and because it's cool to consume locally made stuff, be it beer, wine, spirits or someone's tough, overripe field corn purchased at the local farmer's market.