Defining grooming

OK, given that we are more than half way through Groom Week, perhaps I am a little late coming to the party on this, but I have to ask: why does The Sartorialist tag some pictures with 'grooming', but not others? For example, here is one of his 'grooming' tagged posts.

Here is one without the grooming tag.

With:

Without:

I can't understand it!
I thought grooming was the way people present themselves above and beyond the clothes they wear. Isn't it? Aren't all of these people well groomed? They seem to be to me. What am I missing here?