In fact, in most sci-fi movies where the term 'alien' is portrayed these are usaully more technological, mentally, or even physically advanced than humans. In the movie 'War of the Worlds' the aliens are represented by huge robots who have weapons that we wouldn't even dreamed of. Also in the movie 'The Forgotten' the protagonist is manipulated by 'aliens' in to believing that she never had a child. At the end of the movie, the 'aliens' explain that they have wanted view how the bond between a mother is child is created and if this is as strong as it is believed to be. We may conclude, that in these examples and many more there is one thing in common, the 'aliens' are always superior to humans in one way or another.
Personally, I believe one of the reasons why the author created these "Tralfamodore theories" were only to mock humans. We see this happening over and over again with subjects such as time, life, death and even war. For example on pg. 116, Billy asks the Tralfamadores why their planet is so peaceful. Their reaction to this was very interesting since they looked at him as if he had just asked them what 2 + 2 equalled. This shows that the Tralfamadores are not only advanced and superior to humans but many of our actions or ideas seem utterly useless and senseless to them.
Also at the end of this scene (pg. 115) Billy describes his expierences on the flat car in the zoo. He states " the flatcar sometimes crept, sometimes went extremely fast, often stopped-went uphill, downhill, around curves, along straightaways...That just life" Although he is describing the flat car once he states "That's just life" we automatically create a connection. In my opinion he is creating a metaphor in which he compares the ups and downs of a flat car to those of life itself.