Applying economic game theory to a relationship seems like a good way to take all the fun and passion out of it
But I don't actually understand that objection. Seems analogous to taking Walt Whitman's side in this exchange: http://www.scottaaronson.com/writings/whitman.html
I might have to concede that the whole thing is untenable unless you actually enjoy geeking out about the game theory and mechanism design and whatnot.