The film was allowed to shoot at a real California mall as long as they did not damage any facilities and had removed any traces of their presence before the mall opening time of 9AM. While the mall's head of security didn't like the filmmakers and was constantly accusing them of causing disrepair, the mall's owner was supportive of the film and made sure the production was able to complete its work on schedule.
Filmed in Sherman Oaks Galleria, the same mall used in Comando (1985). Most notably when near the elevators. Both films would've been filmed around the same time, but due to budget constraints, this movie was filmed after close of business.
The special effects crew actually built five remote controlled robots to serve as the Protector killbots. Three were required for the scenes of the robots together in the first half of the film, with two extras as backups in the event that the originals were damaged during any of the action sequences. In order to keep the robots looking realistic (as well as due to the film's budgetary constraints), they were constructed out of such items as wheelchair frames and pieces of conveyor belt. Excluding shooting laser beams, most of what the killbots are seen doing onscreen was the result of the effects crew operating them via remote control.
The movie was originally released in March 1986 under the title "Killbots." It performed poorly and the producers felt the movie's title turned off audiences, who might think based on the original movie poster that it was a Transformers-like children's cartoon instead of a violent exploitation movie. After some time, the movie was re-released to theaters under the title Chopping Mall, with over 15 minutes cut.
The movie Alison and Ferdy are watching is Ataque de los monstruos (1957), another Roger Corman film.