This movie had a dark ending.

First off, I think this movie was really funny and didn't get the attention it deserved. Having said that, I found the ending of the movie to be a little twisted since Fred will inevitably die during the return trip. Here's my argument.

At the very end, the chimp once again gets into Fred's sleep chamber and closes the door. It's reasonable to assume that Fred is unable to open the sleep chamber since he would have done that earlier in the film instead of remaining awake for the 8 month voyage to Mars. Also, upon arrival at Mars, Bill discovers that Fred had been awake for the entire trip and had consumed most of their food supply. How is Fred supposed to feed himself during the return trip? Unless they acquired food on Mars, Fred will starve to death during the return trip. Is there something I'm missing here, or is his doomed?