The difference is: this is a trailer. One generally assumes that an actual story will exist in the full version.
I know, like I said, it's the worse kind of generic bland action trailer that's been used to promote various things.
Look at the Star Trek trailer - explosions and nekked women. I'm sure the original Clone Wars movie trailer had random shit blowing up and Jedi doing wacky things as well.
My thing isn't with the trailer itself, it's with the reaction it illicits from the fanbase.