Central London has lately become home to several snail farms, but they don’t, it seems, produce much in the way of escargots. Officials at Westminster Council say that whenever they’ve investigated these “farms”, they have found that they consist of a few boxes of snails in a vast empty office. But that, it seems, is all it takes to claim that an empty commercial building is an “agricultural facility” – and so exempt from business rates. Westminster Council first became aware of this “ludicrous” tax avoidance three years ago, reports The Times, but it is not exclusive to London. Snail farms have also popped up in empty offices and department stores in Liverpool, Bradford and Preston, among other cities – potentially costing their councils hundreds of thousands in lost revenues.…