Why should you ban the oil spill?

You shouldn't. because it's a dumb and ultimately pointless thing to do.

Banning oil spills is kind of like banning hurricanes. You can do it, but you're going to look awfully foolish the next time one happens because nature doesn't pay much attention to human laws.

Companies don't cause oil spills on purpose... they cost them a lot of money. They happen as a result of accidents, and accidents are, well, accidents. "Banning" them is a waste of time and money.

Laws penalizing companies who carelessly cause oil spills are a different matter, and we already have those.