Although A Christmas Carol focuses on generosity and compassion when it comes to being connected to others, the novella argues for another, equally important motivator for good behavior—feeling guilty when doing bad deeds. A large part of what makes Scrooge such a monster is that he appears to feel no remorse for his cruel indifference and no sense of responsibility for the welfare of others. As he remembers and works through his many bad deeds through the visions brought by the Christmas Ghosts, Scrooge gradually regains his ability to feel shame about what he has done, which means he can police his own behavior in the future.
The unrealistic ease with which Scrooge accepts blame for his past actions has more to do with the fact no one holds a grudge about his behavior than with any actual sense of remorse.
Scrooge's recovery of the ability to feel guilt totally misfires, because it teaches readers that however ungenerous and mean-spirited they might be, as long as they are aware of it, there is always plenty of time to change and be forgiven. Phew.