I get that.

I cannot calculate the likelihood of this because I don't know the bet size distribution.  It would take a large number of high bets (0.5-1% of the betting pool) for this to be at all probable.

It seems weird given the fact that there have been so many bets that you would not be closer to a normal distribution.  However, maybe there is a large number of big bets and the rest of the bets are very tiny.