The term refers to
the culture of leaving work at mid-day, to go to a nearby pub and have a dozen
alcoholic drinks or shots, until the evening, before leaving for home. It is also considered common-practice to put the bill on
the Corporate Credit Cards.
The term originates in view of the exorbitant, careless, even behaviour usually characterised by bankers and traders, at the expense of their clients. It is also often called a Trader's Dozen.