I was surprised to see Susie and that blonde chick on Daniel's court too. You can even hear them cheering for Daniel during the final fight scene.

I gotta watch this again because everytime I see it, I always get confused as to what happened with the neighbor kid from the beginning and how he just vanished from the rest of the film.
When there's no more room in Hollywood, remakes shall walk the Earth.

They were fair weathered friends for sure. Honestly, other than Ali, the whole school seemed to avoid Daniel after his beatdown from Johnny. Even Ali's friends took a strong dislike against him.
I think Freddy was just being a kid. I did similar stuff growing up, bad as that is. Not wanting to be the guy who associated with 'the loser.'
Plus, we're never shown that Freddy outright avoided Daniel. He lived right next door. Terrible friend sure, but he probably cared enough to at least show up and root for him.