lmao, the joke was more about infodumping about one's obscure interests, but as for urine taxation:

Explanation: The Roman Emperor Vespasian decided he needed more income, but didn’t feel raising the proportions of existing taxes was appropriate. So he instituted a new tax - on urine. Urine was used in bleaching, cleaning, and tanning (it’s the ammonia), so it was actually a valuable commodity. Terracotta amphorae were placed around the city of Rome where citizens could relieve themselves like CIVILIZED people, and Vespasian implemented a tax on those who collected those pisspots.

Vespasian’s son, Titus, expressed disgust at the tax, but Vespasian is said to have waved a gold coin under his nose, and told him that the coin came from urine, yet it didn’t smell. From which we get the modern Latin phrase ‘Pecunia non olet’ - ‘Money doesn’t smell’

Also, for this reason, some Romance languages still use words derived from Vespasian’s name for urinals.