[Whiplash Performance]

You should be pissed. Tips are at your discretion but some people don't see it as such.

I had a similar issue at a hibachi steak house, our chef did a terrible job (messed up on the tricks) compared to the others we saw at neighboring tables. The food wasn't good so we left a 10% tip as we were walking out the, managers stopped us and wouldn't allow us to leave until we paid the remaining 10% of the tip. Even after telling the guy about our terrible service and if we paid the rest we would never come back he still insisted on making us pay.