What is the term for being paid to cheer at a concert or other performances.

A plaid pant paid plant.

Or a stooge? I think that’s more like a person that a magician plants in the audience though.

Shill

In Dutch they are called klapvee, which translates to cheercattle.

I agree with @Cruiser: shill.

Laugh track?

http://en.wikipedia.org/wiki/Shill

Here you go:

Claque A group of people hired to applaud (or heckle) a performer or public speaker.

From claquer “to clap.” The practice of paying members of an audience for their support originated at the Paris opera. (dictionary.com)

Renata Tebaldie was purported to hire claques to hiss Maria Callas during her performances.

I like claque better than shill. Shill sounds a bit seafoody

“Shill” and “claque” are not interchangeable.

“Shill” implies that the management wants to winkle money out of the audience, sightseers, passers by; claque is a group hired to cheer or boo a performing artist.

Yes, it seem shill, stooge and plant are similar whereas claque is what @Roby means.
I still think shill is seafoody though, whereas claque sounds like a discordant mix of clique and clap which is perfect. I like words to sound right…