Some of us will remember the pre-plasic glass times. The problem was that the pubs and bars were not too keen on people walking off with pints of beer in glasses that were owned by the pubs. Also, when morris dancing it was difficult to find your own beer after a dance - one pint of beer looks pretty much like another (I always new mine though - it was the fullest glass - always!). Tankards seem to be the obvious answer. Also a friend of mine (Hi collin) used to have a pint and threequater tankard which he used to get away with most of the time (cheeky bugger) untill he was discovered by a local pub who's manager hurled it down the cellar steps on finding out and it broke its glass bottom.