Why Do People Clap At Celebrities?

Question

When they enter a stage. Like in all the sitcomes when someone famous walks in, the "audience" always claps.

Even though they haven't done or said anything yet.

Does anyone know the origin of this?

Answer 1

Sycophancy.

Answer 2

The audience has most likely been coached to applaud at that time. Also, it's like saying Hello! I recognize you! You wouldn't want to walk up to someone and they just look and say nothing.