that should actually be a primary reason to like a movie like Project X. Not trying to offend anyone in particular here but such movies' target audience is namely people up to 18 yo (i.e. high-schoolers or high-schooler wannabies/middleschoolers, whose life is centered at how cool it is being cool) and people, who are older than 18 but have had a hard time growing out of that age range as the being-popular part in high-school played a bit too big a role in their lives and they can't part with it yet and maybe never will.
So, if I was still 15, I am sure I wouldn't have minded the movie, hell, I may have even loved it ... although I doubt it 'cause by 15 I had more important things to worry about than high-school age bullshit. Fortunately or unfortunately, I am way past that age now and movies like this seem like an infinite waste of time. Then again, to each his own.