One: Women would use indigo hair dye called xiuquilitl to turn their hair blue.
Two: In Tenochtitlán human waste would be collected from public toilets for fertilizer. Thus it was someone’s job to sail the “poop canoe” to deliver night soil.
Three: Only a certain type of cacao was used as currency. Counterfeiting was rampant.
Source
Sahagun was one of the first westerners to document the indigenous people of Mexico.