In the scene where Dallas (Matthew McConaughey) finally strips, there is a point where he rolls away from all of the women holding his crotch. This is because the extras got a little bit too excited and accidentally ripped his g-string. Instead of stopping the dance, he just incorporated it in.
The character of Tarzan, portrayed by Kevin Nash, wears a knee brace during his routine and goes with the idea that stripping is all his character knows and is doing it past his prime. This wasn't in the script but came about when Nash showed up on set with the brace on and explained that he wouldn't be able to do the routine properly unless he wore it. Kevin Nash is a professional wrestler with a history of knee problems.
During one of Gabriel Iglesias' stand-up routines, he claimed the less-endowed actors required 'props' for the silhouette dances. When the first box arrived from an adult-novelty store, "everyone's inner twelve-year-old came out" and the cast started fighting each other with them.
When Gabriel Iglesias went to read for the part of the deejay, the producers gleefully chanted his nickname 'Fluffy.' Once they stopped, they informed him the audition was a formality and the part had been written specially for him.