I do find it ironic that we celebrate Labor Day by not working. Not that I'm complaining. A day off is always welcome.
September marks the end of summer, the start of the new school year (for those schools that didn't start in August), and the coming of autumn. Fall in Maryland is a wonderful time—trees turn into torches of bright colors, the air gets crisp and cooler, and is seems like there's always a breeze blowing. The roadside stands sell fresh-picked apples and fresh-pressed cider.
You could also look at it as the start of the Christmas shopping season... 27 days left in September, 31 in October, 30 in November and 24 in December makes 112 shopping days left!