No, he wants to fight all right, but he has to go through this ritual. There's no explanation.
Me, I was taught not to talk back, not to shove back. Yeah right, like that works.
But this was the 80s, and all the real bullies or wackos got involved with drugs and parted ways from me (one of them, I learned later, went into a mental institution). So all that was left was kids who wanted to play bully - and the first time I faced one one them with that 'OK, let's fight' look they all backed down and never bothered me again.
After that, I never again got into a potential fight situation. And people are always extraordinarily nice to me - my wife says that it's because I look intimidating.
So if someone decides to shove me, either he's extremely self-confident or he's got some backup I don't know about. Since I probably won't know for certain which is which, the rational thing to do would be to not fight back. But I can't say for certain that I would act rationally in such a situation.