As far as I understand "Hambones" is more of an insult like "Knuckleheads", because ham bones are thick and solid and in the past would have found their way into soups to be sucked and slobbered over by the peasantry (though lamb/mutton is the traditional ingredient in the cawl round here). I did ask a neighbour this morning and he confessed to having no idea why it had stuck as an insult. He did have a word for those who used it, however - the very Anglo-Saxon "wankers"!