There's a kookie old lady in my old (small) hometown who has been writing about chemtrails in the local paper for years. The problem with most of these theories; moonlandings, chemtrails, crop-circles etc, is that folk hear one long and compelling argument followed by a "My God, that proves it!", when it should be followed by a "damn, that seems to prove it, can I find arguments to the contrary?"

Look at the Fox special on the moonlanding being faked. It's really well presented, it's VERY convincing, and tons of people have watched it gone "OMG! That's indisputable!" But there are those of us who actually researched further, checked the counter arguments and, sure enough, they can blow Fox and their bullshit away.