What is the relationship between Jews, and pennies?

Ok, I like watching Harold and Kumar, but in the 2nd movie, Guantanamo Bay, there is one part I don't understand. I have asked my mom thinking she would know. So we are both wondering, why did Ron Fox (the detective dude) throw all them pennies in front of Rosenburg and Goldstein?? I've never heard of the Jews/pennies thing before.