2. Bruce the Playboy
At the party Bruce invites at least one beautiful starlet to go back with him to Wayne Manor. In a 1980s interview published in a Batman comic, longtime writer/editor Denny O'Neil explained what happens next: Bruce lets all the paparazzi take his picture with the lady hanging on his arm, escorts her to his limo, has Alfred drive them a few blocks, then pleads a headache. He makes his apologies, gets the gorgeous babe a cab, goes off to fight crime and never thinks about her again. Night after night after night. As O'Neil put it, "Bruce Wayne gets a lot of headaches."
Bruce Wayne's social life is a continual exercise in seduction, arousal and dismissal. He charms a sexy woman into going home with him, hugs and caresses her publicly. She's agog, about to spend the night with a handsome billionaire ... then bam! Out on the sidewalk, see you later. This is Bruce's most common interaction with women. Creepy.
What strikes us isn't the routine, callous manipulation; Batman is all about callous manipulation. And anyway, starlets? Who cares? Nor do we dread the prospect these socialites would realistically compare notes and start speculating publicly about Wayne's sexuality. They never will because, again, that's just another story convention.
No, what's creepy is a healthy, athletic heterosexual man who persuades entire job-lots of Gotham City's most desirable women to fall on their back, then walks away, repeatedly, unconsummated. It explains how he sustains the rage to keep beating up muggers.
3. The Mission
Many oddities of Batman's methods arise not from genre conventions but from sensible commercial motives. Though it's heroic that Batman never kills Two-Face, this mercy also lets the writers bring Two-Face back in later issues. Batman wears his ridiculous costume so DC Comics can trademark his distinctive likeness. He can safely let a Boy Wonder charge headlong into gunfire because DC's licensing department needs Robin alive. (Well, one Robin or another, anyway. They're on number four or five now, depending on how you count them.) Bruce Wayne could spend a small fraction of his fortune to buy off all the crooks in Gotham, set them up in nice apartments with a monthly stipend and make the streets safe overnight - or he could pop up to the Fortress of Solitude and say "Clark, mind tackling this little problem?" - but then (duh!) there'd be no more Batman stories.
Similarly, many readers, and even some Batman writers, have speculated the Bat's very existence prompts crazed criminals to take on outlandish identities and commit ever more bizarre crimes. (See, for instance, EcoComics on "Game Theory, Signaling and Comic Book Crime.") If this is true, isn't he part of the problem? This is fun brain-candy, but again, Batman's true purpose isn't fighting crime - it's starring in more and better Batman stories. Fair enough so far.