During the finale, how are both Alex and the spectator rewarded?

Throughout the film, the spectator has been aligned with the central character Alex, whether it be taking pleasure in his actions or taking punishment for those actions as he himself does.  Therefore, we must share his feelings when he is cured at the end of the film.

His Ludovico Treatment is reversed, and he can again take pleasure in ultra violence. The last few seconds presents a dream of his, as the soundtrack of Beethoven plays over and he can now commit what he could at the start. We, the spectator can again take pleasure in his acts.