I had some problems with this episode. I'm guessing Georgie goes out on dates and that he's allowed to have dinner with his friends (if he gets permission first). What Mary should have said was something like, "It's great that you have your own money, but tonight is a school night and we're having a family dinner. You can buy your own dinner on weekends." Mary's problem wasn't that he had money, it's that he was being disrespectful to her.
George wasn't being greedy. He didn't ask for any of that, it was just given to him because the school was trying to keep him there. Also, George knows that Sheldon isn't happy in high school, so maybe college isn't a bad idea. He could have made that case.
I get it's a sitcom and they need drama/conflict, it's just that tonight's episode didn't work for me and fell flat. I wish they had gone more with Mary's concern about her kids growing up too quickly instead of focusing on greed. That could have worked better for me. Maybe Mary's realizing her kids are growing up and that scares so she goes crazy with family related church activities, or just family/togetherness type stuff in general.