Exactly. Did he play with any accompaniment? Was his music upbeat or slow? IMHO if you want to either be ignored or end the night then all you have to do is play three or more slow songs in a row. Even if people request nothing but slow stuff at a piano bar (they often do) you have to mix the songs/tempos to keep it lively and interesting. And having accompaniment so you can do some faster jazz trio swings makes all the difference.

I play a piano bar on Friday nights and inevitably somebody wants to hear "My Way" or something like it almost as soon as I start playing... I refuse. I tell them that I will play the slow stuff after I liven the place up a bit and they usually understand that.