By developing stronger bonds with your students, and making them feel valued, you will have to deal with less misbehavior. If you want kids to listen to your message, they have to like the messenger.
Extrinsic reinforcement can destroy inner motivation.
Kids who don't get rewards may act up out of resentment toward you for not noticing their prosocial behavior. Kids' self-esteem becomes dependent on the approval of others, rather than their own self reflection. That's a question often asked by teachers and parents. The reaction could be their way to retain autonomy and self-dignity. Perhaps you've praised the character of the youngsters rather than their actions.