Low fat. Reduced fat. Fat free. American society emphasizes that thin equals beauty, and people will go to great lengths to eliminate fat, even having it sucked right out of their bodies.
This fat is critical to Tyler's soap making process. He steals fat from liposuction clinic dumpsters labeled "infectious waste." And boy does this scene really play up the gross-out value. The fat is wet and gooey, stored in plastic bags that rip on barbed wire, spilling lumpy slop all over our main character. Blegh.
Tyler uses the lipo clinic fat, the "fat of the land," to make soap. Not just any soap—super-duper luxury soap marketed towards women:
NARRATOR: Tyler sold his soap to department stores at $20 a bar. Lord knows what they charged. It was beautiful. We were selling rich women their own fat asses back to them.
Here we get Fight Club's scathing social commentary on two fronts. It critiques society's obsession with beauty and plastic surgery (even as it manages to be pretty fat-phobic) and it critiques society's obsession with luxury goods. These rich women are buying soap that costs more than twenty bucks. Soap. That's insane. And Fight Club puts this insanity on display so we can laugh at it…even as we carefully read the ingredients on our own bottles of bodywash to make sure that "human fat" isn't slyly listed between "lavender extract" and "water."
Tyler Durden calls soap the "yardstick of civilization." He makes it and sells soap it to department stores, and we're told, "it was beautiful." Who doesn't like soap, besides Pigpen from Peanuts?