Cask ale requires a great deal of effort on the part of publicans to maintain and serve correctly. This is something I touched on briefly in one of my earliest posts about The Harp in Covent Garden.
The vast majority of ale drinkers in the UK do not even appreciate the importance of proper cellaring. When speaking to them, all but the most beer savvy of them would attribute bad condition and off flavors to the brewer. While it is at times the fault of the brewer, my experience has been that it is far more often a result of the publicans failing to properly keep their cellar.
So why is it so much more onerous to keep a cellar full of cask than keg? Firstly, beer dispensed from a keg is almost fully devoid of oxygen. Carbon dioxide is forced into the keg during filling and is also used as the pressure mechanism to dispense the beer through the line. Cask ale, on the other hand, uses suction or gravity for dispense. Beer flows out one end and ambient air flows in the other. The oxygen will eventually stale the beer and there is also the danger of infection via exposure to whatever micro-organisms happen to be in the air. Practically, what this means is that the shelf life of cask is vastly shorter than keg. A cask will only last several days after venting, while keg can sometimes last several weeks. Pubs with low turnover will find it nearly impossible to make money off cask because the spoilage can be high if it is not consumed quickly.
Second, cask ale is alive. What I mean by this is that cask ale contains live yeast that is constantly changing the condition of the beer. The brewers put the beer in the cask, but it is up to the publican to manage the secondary fermentation. Cask ale, therefore, is not a passive enterprise in the way that keg beer is. In order for a cask ale to be served properly, it needs to be stilled, vented and checked for proper clarity and condition. This all isn't very hard in theory, but it still takes somebody knowledgeable and willing to do the job suitably well.
Here is a spread of four of my ales that were on tap at The Bull in Highgate. It would be wonderful to see cask ale occupy such a prominent place in pubs across the States.What this all boils down to is that cask is much more difficult and expensive to keep. In my opinion, there simply is not enough demand to give publicans the impetus to invest in cask ale. Sure there are breweries that cask their beers, but what little is casked is generally served at the brewery or at pubs operated or closely affiliated with the breweries themselves. And sure there are pubs in the States that specialize in serving cask ale (and serve it very well), but those are few and far between. Cask ale is a tradition in the UK and that is why it exists. American craft brewing simply does not have the tradition, but it does possess an extraordinary exploratory streak. This may bode well in the future, but I still do not believe cask will gain a real foothold for quite some time. Even with some demand, publicans will not invest in cask and people will not drink cask because the quality is likely to be low on account of poor celaring. I hope I am wrong, whatever the case may be.