"Do Make It a Good Day"

       There's a department at Kaiser Permanente which leaves a phone message to remind you of an upcoming appointment.   The nurse always ends with the same few words:

       "Do make it a good day."

       That stops/me/in/my/tracks/.  How different from just "Have a good day."
   
       Both sentences are imperative with an implied "you" as the subject, but "Have a good day" rings for me as "(I hope you experience) a good day."  "Make," however, with its auxiliary verb "do," creates a special message and emphasis:

       "Oops!  This "good day" is up to me?   I can cause it to happen??  Indeed, that's the only way it will???"

        That message helps me turn my day in a better direction, and I don't see how it wouldn't for anybody.