Before kids, it used to be the late showing of Buffalo Bills, or Dinner in the Steakhouse, California Grill or Annette's, maybe KIng Ludwigs. A little shopping. Some swimming. Cocktails in one of the bars (at least once at the DLH and they have a non alcoholic one in a souvenir cup for your 8 year old). We would often be found dancing or watching the live music at Billy Bob's. Also games, bowling and IMAX are good fun at night too. Don't forget a trip up in the Panaramagique Balloon.
Now we are parents, if the park closes at 7, it is a stroll back to the hotel via a shop maybe or a cocktail, then bath and bed ready for the 6:30 wake up call.