I'm torn, but what i did notice, and the wiki makes mention of it, is that Locke looks around the room, for quite some time, before he 'sees' Anthony Cooper. Perhaps it was those few seconds that smokey formed, having read that Locke's closest harsh memories at that point were the old bastard conman.
The only other logical explanation is that locke is going through the same thing that we saw Desmond go through in Flashes Before Your Eyes. the Others know Locke, but he barely recognizes them, because he has done this before, and his anger ruined it somehow. This time Ben, who likes Locke, grabbed Cooper before coms went down and held him until that very time. Locke has basically made the decision to stay onthe island, and Ben is rewarding him for doing so.

you can't beat that with a bat!