Alexandra asks Miss maudie,"what else do they want from him, Maudie what else?" What does she mean by this question? to whom is she referring with the word they?

If you examine the rest of the quote, it becomes clearer,

“I mean this town. They’re perfectly willing to let him do what they’re too afraid to do themselves-it might lose ‘em a nickel. They’re perfectly willing to let him wreck his health doing what they’re afraid to do, they’re-”

Aunt Alexandra is referring to the town asking Atticus to defend Tom Robinson and then torturing him.