Sometimes it pays to read the fine print.
It is amazing what rules and technicalities can be buried in a contract or handbook that most people never thoroughly read, and often the best time to do so is when somebody who should know better is going against that for their own benefit.
In particular, the workplace is somewhere in which everybody wants to make sure that they know what they are allowed to do, and how that matches (or does not) with the demands of their superiors. There are plenty of bosses out there who are reliant on the idea that their employees will value doing right in their eyes above their own legal rights, and it can come back to bite them.
We might go as far as saying that when employees face an unfair restriction at work, one of the first places they should turn are the official rules of the company. It might be surprising what they find.