They were supposed to be the typical bully stereotype. Bullies usually believe that anybody smaller than them are inferior to them and therefor treat them such. Because Hyp and his friends are bigger that Littlefoot's group, they naturally treat them like dirt, maybe not that extreme but you get the idea.
The only thing I didn't like about this review was how he skipped through Kids Like Us. That song is actually one of the better songs in the franchise, and he skipped it over mainly because the previous two songs were terrible. Of course, I agree that the previous two songs were of poor quality, and I found it quite humorous how he substituted Topsy's song, but he could have at least shown that the final song was a change of pace and was a more meaningful song.