> They're cheating at the normal hiring practice, not allowing other candidates in, because they think it gives them some sort of advantage.
No, they're not "cheating," they are taking a shortcut to a known good candidate so they can get their job done quickly. If you need an employee and you know of one that would meet your needs, you have no obligation to search far and wide just in case there's someone else who's just as qualified out of some sense of fairness. The fact that some organizations behave as if that's a requirement is simply a self-imposed (or sometimes contractually-imposed by some other org e.g. via government contract) safety mechanism that helps reduce the opportunity for corruption (or the appearance of corruption).
No, they're not "cheating," they are taking a shortcut to a known good candidate so they can get their job done quickly. If you need an employee and you know of one that would meet your needs, you have no obligation to search far and wide just in case there's someone else who's just as qualified out of some sense of fairness. The fact that some organizations behave as if that's a requirement is simply a self-imposed (or sometimes contractually-imposed by some other org e.g. via government contract) safety mechanism that helps reduce the opportunity for corruption (or the appearance of corruption).