Without building an army of robots Spongebob and Patrick would have nothing to stop. Plankton helped fill their day with fun and exercise . Without that fun Spongebob and Patrick might have become bored and depressed. He single handedly saved them. And since Plankton is a Genius he could make an atomic bomb at any time, but why doesn’t he. because Plankton cares, Plankton is a hero who loves his wife and kids. He even had a pet amoeba. And isn’t that what a hero is, A good person that helps people. He makes his food terrible, and tries his best to make it good, if his food was pretty okay less people would go to the Krusty Krab. where Mr.Krabs gets them addicted to a ‘Krabby Patty’ a burger so addictive Fish die from consuming too much. What would make Mr.Krabs a good guy, Exactly HE ISN’T Mr.krabs is a greedy dirtbag that pays Spongebob less than a dime a day. He only cares about Money and tried to break a mans arm for a single cent. And where does this money go? Mr.Krabs obviously a cocaine addiction, that’s why he need so much money and remember that episode where he boiled an “Egg” and his eyes were bright red. Mr.Krabs is the Villain enslaving countless fish with an addiction, Plankton is the actual Hero he tried his best to take control away from Mr.Krabs