Wikus Van De Merwe: This whole's thing's under your shack? For 20 years, you've had this fookin' thing hidden out here? This is, this is very illegal, I mean, this is... This is a fine.
Automated MNU Instructional Voice: When dealing with aliens, try to be polite, but firm. And always remember that a smile is cheaper than a bullet.
Wikus Van De Merwe: I'll send you home in a fookin' jar. Go!
MNU Agent: We need your signature on this eviction notice.
Angry Alien: Fuck off!
MNU Agent: MNU! We're serving eviction notices.
Alien: What is "eviction"?
Fundiswa Mhlanga: He was an honest man, and he didn't deserve any of what happened to him.
Wikus Van De Merwe: Could you go a bit slower with the clicks there, it sounded like you said *three years*.
Police Officer: I mean, you can't say they don't look like that, that's what they look like, right? They look like prawns.
Wikus Van De Merwe: Get your fokkin' tentacle out of my face!
Answer: This isn't actually remotely uncommon. Trailers are almost invariably released before the final edit for a movie is locked in place, so it's not at all unusual for shots in the trailer to be from scenes that ultimately don't make it into the finished product, or to be from alternate takes of scenes that do appear. As to why this particular scene was rejected, who knows, most likely was just for pacing, or they might simply have not liked some aspect of the acting or whatever.
Tailkinker