It just runs counter to my own experience and observation. Deflecting the request with a joke would be an effective way to avoid getting played for free drinks, if you think that's what's going on, or of politely declining if you're just not interested, but it doesn't seem like a generally effective, or commonly practiced, method of actually parlaying the interaction into a "score" - not unless you happen to be dealing with the kind of person who's attracted to assholes. My impression is that these kind of PUA style techniques are geared towards successfully picking up people with low self esteem. That may work, but I think it's a mistake to draw conclusions from that about "normal" social interaction.