He pointed out that the pro isn't the direct ability to hack social network accounts, but that the ease of such things pushes others to be more secure. Of course, you're more than welcome to argue that that sociological pro isn't worth the cost. And, honestly, I agree that it's now. But it's a reality that such programs happen, and while they do, he's pointing out that there is a positive side-effect.

Ideally, this wouldn't be an issue in the first place, of course.

I agree with you, however I want to point out unlikely scenarios that do still happen, where this could easily be relevant:

Suppose the account being hacked is of some school's local gang member kid / vicious "bully" (hate that word, it sounds WAY too benign), etc., and he and his buddies were discussing jumping some kid and beating him up in the near future, etc. And you happened to overhear of it, and given that this is teenagers we're talking about, they could easily be expected to have facebook accounts, and be stupid enough to discuss such activity over them. Anyway, said hacking could easily get you evidence needed to anonymously tip off authorities, or to deal with the situation on your own (which, sadly, is sometimes more effective... often a LOT more effective, depending on your luck with the authorities in question, and your skills and connections otherwise..).

Or, suppose you yourself are the victim of something at the hands of a person - let's say you're female, and have been raped by some *******, who is still threatening things like blackmail and the like (or, as is often the case with rapes, especially in high school, you'll get raped and then the ******* goes around telling everyone that you willingly slept with them, etc. For all you know it was a drug-helped rape and they took pictures during the act and are distributing them, etc). Now, the average rape victim goes through horrible trauma and only some are able to seek revenge or any sort shortly after the event, but given how difficult it is to get convictions when dealing with rapes, being able to access private messages could be helpful in terms of evidence later. I can also think of quite a few other ethical ways that hacking can come in handy when dealing with people heinous enough to rape someone, but I don't want to bore the people who actually read what I write more than I already do.

Or, you know, there countless other ways you can use facebook hacking, given how much communication happens over facebook nowadays, towards ends that are ethical in context of that hypothetical situation.

Now, I'm not necessarily saying that justifies the existence of programs like this - obviously far more abuse will happen than legitimately ethical use - it's just that the cons/pros of such a capacity existing in general came up, so I felt I should point out that pros could happen.