This Labor Day box office, The Weinstein Co opens Dimension Films’ Apollo 18 in 3,328 theaters while Relativity Media chums Shark Night 3D in 2,806 locations. But also Disney/Pixar is expanding the run of Cars 2 this Friday for special end-of-summer return engagements at a total of 2,043 theaters. (The toon, which opened June 24th, had only 233 runs this past week.) Meanwhile, Lionsgate announced national sneak previews of its movie Warrior, starring up-and-comers Tom Hardy and Joel Edgerton before its September 9th release.