The Southern habit of putting the word now in the middle of the phrase, "Y'all come back now, ya here?" doesn't really make sense to me. Do they want me to turn around and come back inside? But, their habit of dropping now at the end of, "You have a great day now" is decidedly pleasant. I suppose in theory, I could be having a rotten day, and as I lay down to go to sleep the phone rings, my bank calls to inform me I've won some sort of raffle, have just aquired $1,000,000, and I could still call that day "good". But by saying, "You have a great day now" it's like they have requested that my day immediately become a good one, and that is something I can appreciate.