Certainly you don't have to have them, but if you can afford them - go for it. If you really want an advantage, go for the thru-hull lights.
They attract bait and you'll love what you see at night. Also, and probably my favorite reason to have them is the advantage you get for handling fish at the boat in the dark. Having leadered one over 240, I can tell you they're crazy at the boat and a 4' spear slashing around in the dark could get pretty hairy!