'tis merkin
and to be an horrible racist, they do tend to labour the point, whether laughing or clapping or hugging or jumping for joy or close up shots of facial expressions of disgust, confusion, surprise etc. The reality shows are much worse for this.

One thing I think deserves to be mentioned, that although it might be filmed in front of a live audience, the reactions are 'normal'. The producers are quite clear at the filmings that they want the audience to react strongly, so the reactions are even more over the top than they would normally be for an LA audience full of failed actors.
( Sextant goes to him is emotionally erect, on this day, Sat 13 Aug 2011, 23:34, Reply)