Though unaware of her motives, Jack is comfortable with a certain amount of mutual deception. Everyone lies, himself more than most, and it would hardly be fair to expect any different from anyone else. So he doesn't. He accepts what he sees, which at the moment is a shy and presumably attractive woman in need of drinking advise.

"Where did you come from? To help me decide." And not because he's chatting her up or anything, clearly. The bartender is having a heck of a time back there, so they have a minute.