Why can't you be like that all the time?

Have you ever noticed how people try to be forcefully or overly cheerful at the stores this time of year. I bought a gift certificate yesterday and I was about to take my bag and head to the car and the cashier stops me and says ," OH, I ALMOST FORGOT, I have a special coupon to give with your gift certificate." Now, would he have done that if I bought the certificate in July? If only people could be cheerful all year-round. Maybe I will keep wishing people a Merry Christmas even after it is over.