Second, nobody said "tell your players you aren't fudging", I just pointed out that if you were not fudging and then shifted your stance to one were you allow occasional fudging not only is it not something you probably need to bring up, but that it would be bad for the game to do so, generally.
2.) Even depicting the DM/Player relationship as Older/Younger kids is a bad analogy, because you're creating the image that one is "punching down". Which isn't really the case, they have different roles, it's not about a relationship of in-equals, it's more like the difference between what the rules for a director vs. what the rules are for an actor. Or similar, they don't have the same job, so the rules shouldn't be identical to them. And it's not always in the DM's favor, for example, a character can be completely selfish in their character goals, a DM can't make an NPC that is like that or should not. The rules are different because the roles are different.