If that's the lens you're looking at candidates through -- as people auditioning to be your friend -- of course you'd feel you're obligated to help them through their job search! That's what friends do for each other.
But the people who work for you -- and even more so, the people who have only applied to work for you -- are not your friends. You can (and should!) be friendly with them, of course; but you can't have a real, true friendship with them, because you have power over their lives that they don't have over yours.
Moreover, if you try to just ignore that power differential and relate to your employees like they're your old dorm buddies, all you'll find is that the power differential poisons the relationship. They'll constantly be second-guessing their own reactions to you, out of fear of negative job consequences. You'll constantly be second-guessing your own reactions to them, out of fear of appearing to play favorites. And they'll all be second-guessing each others' reactions to you, out of fear of someone brown-nosing their way past them on the career ladder.
It's the same reason why it's always a bad idea to date someone who reports to you -- you can never have the kind of relationship with them you have with someone outside the hierarchy you sit at the top of. Suspicion and jealousy and gamesmanship taint it from the moment it begins.
The solution to all these problems is to learn, understand, and internalize the distinction between colleagues and friends -- two groups of people you owe very different things to -- and then act accordingly.