The right wing nuts hate the idea of anyone but themselves being firearms proficient; it ruins their premise that they are the only ones who are knowledgeable about firearms, and therefore the only side of the controversy that should be given credence.
We've seen this in the hysterical and hilarious efforts at "skeeters" trying to gin up stupid alternative reality and revisionist history.
We have Alex Jones''Infowars' spreading a conspiracy theory because Obama may have changed clothes on the date in question. The New York Magazine came up with a review of the whole spectrum of conspiracy theories, including those about how level the gun is and the smoke pattern. So, nothing could be more fun than to mock the "Skeeters" with a parody of them using JFK.