I think i figured out why they named Hercule from Dragon Ball Z, Mr. Satan. His first appearance is when Cell shows up and says he'll destroy the world, so naturally, people panic. Then this guy, Mr. Satan comes out of nowhere, saying he can defeat Cell and everyone loves it. I think this shows how, when people are scared, they try to find any way they can to survive, in this case, praying to the devil, Satan. Even though he can't do it, people still believe in him, and he becomes famous for being a liar and a crook (stealing the glory from the Z fighters). So either this is just my imagination, or genius writing by Akira Toriyama.
TL;DR, Hercule is the Devil.