Wow, Oli is going to be delighted (as will be Comet, because stuffed toys! I am afraid Oli will have to indeed be a little stricter with him now. Percy will be happy). And I have a feeling that, if they all dress up for Halloween, Oli might be going as a Cowboy. :D Al would definitely get a hug in thanks.
Oli will also be happy about candy, since he pretty much gave up on his diet plan and can enjoy all the candy he wants. He will also be glad Draco showed up for Quidditch.
As for Mike, he'd thank him for providing the food next time he sees him. Which would most likely have been Monday evening, since Perce and Oli picked up some food at his place.