I don't see anything wrong with a romantic subplot if it's well done. Unfortunately the landscape of film is littered with so many poorly done conceived and shoehorned in ones that a large section of people react violently to any semblance of romance in a non-romantic movie. Which is a shame, because a well done romance can do a lot for the characters and stakes of a film. Just wish there were more good examples so people wouldn't be so quick to dismiss them out of hand.