It's probably more then just being smart enough to realize that we're not worth the effort - Orca echolocation presumably gives them a comprehensive insight int

It's probably more then just being smart enough to realize that we're not worth the effort - Orca echolocation presumably gives them a comprehensive insight into just what's going on inside us regarding composition. For them killing sharks I'm sure it wasn't killing a few for kicks until they discovered the liver's were tasty. It was probably more like seeing hamburgers walking around.