Lately this meme has been going around, illustrating how you are more likely to be killed by (among other things) a vending machine than a shark. I don't know how accurate their research is, but the fact still stands: the odds are highly in your favor of having a shark-free surf. But still I know many people who are reluctant to even try surfing because they are afraid of shark attacks.
What I usually tell these folks is, "Think of all the people that go surfing in the world, every day. Now how many shark attacks do you hear about?" Few to none. But when you're on the open water, in "their" territory, it's not hard to imagine a big fin popping up in your peripherals, or a giant shadow gliding underneath you: