Not for nothin'. humans have only been around for a few thousand years...the universe is 13.7 billion years old. They are low-man-on-the-totem-pole when it comes to civilizations, many of which have visited, continue to visit, and have become enmeshed within over long stretches of time. As it is, in just the past 100 years, mankind realized that the universe is much bigger and older, and that each star out there pretty much has a system of planets, the most common red dwarf stars.
Could be this planet is a "game preserve," as so far, these beings keep their distance (can you blame them? Humans can't even get along with their own, let alone other creatures) but haven't yet decided to blow humanity off the face of the planet.
That said, it's unlikely a star-faring civilization would retain a predatory nature and more likely they've evolved beyond the need to prey on lesser beings.