Yes thats right, it's not the Predator homeworld it's a huntig reserve. Its the same as we have africa and other hunting areas. So just think of it as we have Africa but on a different planet.
As for the trailer i am very impressed as i can see that this movie has a very impressive atmosphere. The characters arent made from cardboard like Avp2. I realy like the ending as in the other trailers when you hear that high pitch sound followed by a new predator scream Other people have commented saying the dont like how they have changed the sound of the predator, i for one dont find it so bad, after all some of the predators are a different species (BSP)as to what we saw in P.1 and P.2 and the Avp movies