It's more like guidelines anyway
The first rule of the druid code is that you don't talk about the druid code.
Second rule is! Be nice to mommy!
Quoted and sourced no doubt
Druidity is a real religion my freind is one. It is like Ghia's paganism. The balance, all Druids strive to be neutral. Too many deer? They eat deer, too many people? They remove people. They technically eat anything nature provides as long as they maintain the balance. Eating grass and trees and stuff isn't a Druidic tenant, they aren't sheep.
1. Druids in DnD are not real world druids.
2. Druidism died out a thousand years ago, give or take a few centuries.