I get it. It's pretty annoying when a celebrity begs for privacy or bitches about the paparazzi one minute, then, say, invites photographers to watch them make out the next."This is what you signed up for," we bellow back, eagerly refreshing our browsers for the latest pap snap. And yes, some stars do seem to be hell-bent on courting attention 24/7. While others take a more strategic approach, coming out of the woodwork only when they have something to promote or spin.Though, we can all agree on a few rules of etiquette. Ambushing people and baiting them with inappropriate questions is messed up. Spying on celebrity kids and taking their photo without their famous parents' blessing is messed up. Creeping on a singer who is a) ill and b) sleeping is messed up.That last one has just happened to former One Directioner Niall Horan . The Irish pop star was on a flight to the States when a fan approached him for a selfie. According to Horan, he declined, explaining that he was under the weather. What did the fan do? Wait for him to pass out, take a photo anyway, and put it on the internet.Horan, who has been vocal about harassment from so-called fans in the past, took to social media to call out the person who invaded his privacy."I think this shit is unreal," he tweeted. "I mean if you can't sleep on a plane without people taking photos of you, what can u do?"