Have to say although I like the pub at Victoria, above WH Smiths I do find myself moving the Point of Sale they place to obscure the till showing what change to expect and also leaving my hand out until I've checked my change. A particular favourite is the £3 change which is actually 2 x £1...
To be fair, you don't need "one-under", I often pop in when I'm in the big smoke getting a train back before the rush hour, say around 3.30 and it's packed then. Although rents are very, very high.