Even Harry usually has a bit more tact then that. I mean, he can and often is a colossal asshole--Summer Knight is a good example. After causing a war that had just killed a lot of wizards, he shows up to the meeting to discuss what happened...wearing a bathrobe, with bad hair, unshaven, and generally looking like a huge mess, showing his enormous respect for the lives his actions took. Is it any wonder the Council doesn't like him? If he was in the army or something and had just done something like that, the response would likely involve big burly men waiting for him in the parking lot. Like many of the things he's done, it doesn't look good from the outside. But there were reasons. He was a mess over Susan, he'd had a really shitty day, his cat fucked up his formal robes, he couldn't speak Latin, etc. He still looked like a colossal douche, but at least there was a cause. Similarly, while Harry's often a dick to...everyone and an irreverent asshole, he's usually not the type to actively try to be a heel to people that are doing their best to protect people, to young girls (or girls in general), and especially not to both. Him doing so here is a huge flaw with his character and also irksome from the perspective of someone on the outside, because it's undeserved dickishness.