You don't get it?

I think these people may be looking for something that isn't there. The punchline is not as good as the set-up and this can confuse and irritate some people. Similar to the ending of No Country for Old Men. The amount of people who seem upset by no real conclusion is bizarre to me but I can see why they are disappointed.

Also in The Prestige [spoilers]we are constantly told that Bale's character uses a double. So when the twist is revealed that he actually DOES use a double some people think it is a bad twist and completely ignore the "You're not really looking, you want to be fooled" parts of the film.[/spoilers]

If you make a feature length documentary on one joke told by so many different comedians, the majority of people will expect a joke so funny that their heads will explode.

SnakesOnAnAfricanPlain thinks biscuits are racist, homophobic and sublimely stupid.