Most notaby, this was done when an animal was killed for food.
Does the Bible mention any other times blood is to be poured onto the ground? How about when an animal was killed in self-defense, but not eaten? Did it only apply to mammals? How about birds and fish?
What about people? Does the Bible ever speak about a person's blood being poured out, other than metaphorically?
How does the society make the jump from animals killed for food to human blood?
I have to take my son to his taekwondo class now (gasp), but look forward to any replies tonight.