The worst culprits are the Pub Co`s. Beer is not that expensive if you can buy it on the open market........but very often even Leaseholders are tied to a single supplier for their beer and pay about a third more for their beers as a result, and the Pub co`s, as Gareth suggests are simply property companies, out to make the maximum income from their holdings. Often with a very short term view as well.
Rents are generally horrendous and make no allowances for fluctuations in trade, despite the fact that Leaseholders have often paid large sums up front to buy the lease. You only have to look at the number of boarded up pubs and pubs for sale in most parts of the country to see how little money there is in the traditional "Local" these days. Also look at the cost of buying a "Freehouse" in a popular area for drinkers........Lottery winners money!! And then there are the Pub Supermarkets like Wetherspoons, (I heard that even they are struggling to make a profit!) who are also creaming off a great deal of trade.

Support your Local........!!