Why would an organization choose to sell an asset and then lease it back?

They would sell the asset to provide them with capital.Once the asset is sold they don't have any of the overheads associated with the asset so less costs and also they will increase there capital budget. It is then common to lease the asset back as this retains the asset's usage.

Common example is pubs, brewery's in recent years have sold assets such as a pub to create capital that can be invested elsewhere and then they lease the pub back without any of the overhead costs.its basically a paper excercise to make organisations look more attractive.