How did Henry help the others in the book Dry?

I'm not entirely sure that this entitled rich kid helps anyone in the story except himself. Right from the get-go, when Kelton and Alyssa try to get Uncle Basil's truck back from Henry, Henry shows himself to be selfish and uncaring. He promises to give back Basil's truck—and throw in a case of bottled water—if Kelton and Alyssa will take him with them. But Henry knows full well that there's absolutely nothing inside that case but some old advertising brochures. So much for being a help!
Later on, Henry helps himself by selling the truck to a couple of men for a drink of water before running off. He'd have us believe that he went to rescue trapped residents of a nursing home, but that's just a lie he tells everyone to make himself look like a hero.