I mean, tossing candy out of the window is littering. Unless you are the kind of parent who allows your kids to litter they will pick up on this inconsistency.

This is the cardinal mistake many parents make: They assume you can just tell kids how they are supposed to behave, and they will somehow extract the right lesson from your words and learn it.

In reality kids observe and learn from your behavior. That means the lesson here could as well be: "If you are the stronger one, you can make the rules. And the rules don't have to make sense and if you are in the right position you can break them yourself and be mean to others."

Which is ofc the polar opposite of what you sought to teach them. If you reason with your kids even of they are unreasonable, you teach them that reasoning is a good way of dealing with problems. If you explain to them why they are not allowed to do certain things you teach them there are reasons and they should be curious about the reasons behind the rules.