I don't have to trust anything, that's just the way it is. Just like people often fear sharks, even though they would not normally attack you. They don't tend to eat humans (we're not on their ecological menu) and if they attack, they do so because they were threatened or you got too close. This is nature 101, people.
That, and mistaken identity; Great Whites are actually incredible cautious and docile when compared to their more aggressive cousin, the Bull shark; some of those have developed a taste for human, but for the most part, you're right; we're not a main part of their diet, so they don't actively seek us out. If someone is in a wet suit and gets attacked by a Tiger or Great White Shark, I guarantee it was mistaken identity (I've done way too much learning about sharks, thanks to my mom having an intense interest in them). O_O
Likewise, the Orca thing; I think there are cases of them attacking humans (without understanding what specifically provoked them) but it's not as common place as people believe; they hear the name, "killer whale", and the worst is assumed; they kill, yeah,
like every other predatory beast on this planet-us included. But more to the point, their name had nothing to do with attacking humans, and everything to do with the wide assortment of prey they hunt. Some pods even have favourites, as far as foods go; some go after sharks more than anything else, others prefer seals; depends on the region, I suppose.
Doesn't mean I'm going to jump in the water with a pod of Orcas, however. Hell, I wouldn't even do it with dolphins. Animals aren't intentionally cruel, but it wouldn't be wise to underestimate them, nor to forget what their capable of, either; they are what they are, and are deserving of our respect.
