You would be too if you were constantly living in the shadow of that statuesque drink of water the Brontosaurus.
Imagine you come home from a long day at Jurassic Park. You just mauled another annoying paleontologist and he gave you indigestion plus your boss is all like "MORE CARNAGE, MORE CARNAGE" and you feel like telling that prick off but you bite your tongue and obviously it bleeds, you know, cuz your teeth are razor sharp. Basically it's another bad day. All you want to do is have a beer and hit the sack but you can't because there he is- your neighbour. Look at him standing there, glistening in the sun, eating the leaves off the top of the tree and getting all the chicks. His pad is better than yours, his clothes are better (well they would be if dinosaurs wore clothes), hell even his kids are better.
He's a constant reminder of your inadequacies and all he did was be tall and handsome.
So you go over and make a meal out of his family. Mostly because it's instinctual but also kind of cuz you have small
It just goes to show you that the struggle of the tall and handsome has been going on for millions of years.