Comment by klingoff

Firing people at will includes firing them because you got the feeling they may be behaving in any way in any situation perhaps in conflict to any request you made. Odds are someone won't get fired for stealing office supplies and in at will place they may be more often fired for misunderstandings related to a misperception where they don't come clean on something they never did.

That there was no way to sue the company in that example is a demonstration that the employee lacked any right to break any taboo.

As such there are teeth anywhere that is at will for any request whether it is reasonable or not and whether it relates to a taboo the employee may be expected to have or not.