Other mistake: Walter Paisley is cleaning the floor and encounters the first robot. The whole reason the robots are patrolling at this point is that the shopping centre is supposedly closed to customers, as it is nighttime. However in this scene you can see quite a few people shopping on the upper tier of the mall above Paisley.
Other mistake: When Allison "crashes" into the paint store near the end, she merely leans against the glass and it instantly shatters, which would not happen without her swinging something extremely heavy or sharp against the glass.
Other mistake: When Mike and Leslie are fooling around, another moment cuts back to them now sitting up in bed, and her mouth covered in perfect silvery lipstick as she rummages through her purse for smokes. No way did she had time to reapply her lips after just having sex.
Other mistake: When Allison runs into the pet store to escape the killer robot, she passes by a tarantula aquarium on her right, before crawling in to a hiding space below some dog cages. When the killer robot crashes into the pet store after her moments later, it knocks over two aquariums on the right, and one on the left.
