There is an old hotel/pub in Marble Arch, London which used to have gallows adjacent. Prisoners were taken to the gallows (after a fair trial of course) to be hanged. The horse drawn dray, carting the prisoner was accompanied by an armed guard, who would stop the dray outside the pub and ask the prisoner if he would like “one last drink”’. If he said yes, it was referred to as “one for the road’. If he declined, that prisoner was “on the wagon”.
They used to use urine to tan animal skins, so families used to all pee in a pot and then once a day it was taken and sold to the tannery. If you had to do this to survive you were “piss poor’. But worse than that were the really poor folk who couldn’t even afford to buy a pot. They “didn’t have a pot to piss in” and were the lowest of the low.