Alice is really popular at Fictional High. She has an impressive crew of friends, and there's not a boy in the whole school that doesn't want her. We know this. Except we really don't. Her "huge crew of friends" is really not more than three or four girls, and there's apparently only one boy in the entire school, maybe two. So why does the incredibly popular girl appear to have no more friends than the Cool Loser? In live-action or animated works, the answer is normally money: if you want your Libby to have more friends than you can count on one hand, it will probably turn out to be incredibly expensive to hire actors and voice actors to play the parts. In written works, this occurs because the author doesn't want to confuse the reader with loads and loads of unimportant characters, and will probably avert this trope when the characters are important to the plot. Often happens to The Libby, but occasionally happens when one of the protagonists is supposed to be popular. Compare and contrast Cool Loser, who is a loser for the same reason.