A few hundred years ago,the best chemical to burn hairs off cow hides,cattle. Was pi$$,the ammonia in it dissolved the hairs leaving the leather,hide ready to use for shoes,clothes. So family’s had a big chamber pot,that everyone pi$$ed in,hence the saying,pi$$ing in the same pot comes from. They then sold this. But some families were so poor,they couldn’t afford a pot. Hence,they didn’t have a pot to pi$$ in.