While it's true that, as hank says, some of "these people" are scammers motivated by greed, over the years I've encountered a number of them, especially among "Martian anomalists", that I'd diagnose as just loving science too much.

A stalker's kind of love, to be sure.

You see it in a typical trajectory, starting with starry-eyed hero worship and a burning desire to "contribute" (puppy love), followed by rejection and bitterness (growing up); and in some people, graduation to the passion to prove themselves worthy of their unrequited lover's regard (obsession). The impulse to demonstrate scientific cred in an emotional atmosphere of resentment has a way of leading to cargo cult science.

Dr. Joseph's web site is a brilliant example of the genre of somebody sincerely and passionately at the fringe. I'd be careful about calling somebody with a doctorate a "pseudoscientist" for fear of a lawsuit, but I think that given the amount of material on his site having to do with NASA conspiracies and persecution of "heretics", Joseph might be comfortable being labelled on the "fringe".

But I came away from a half hour at his web site and following google links convinced of one thing: The guy is sincere. He's not one of hank's cynical hucksters. He believe in his ideas, and while he seems to be making money from book sales and the like, activities like that don't come close to making the case for fraud. Being supported by your work isn't prima-facie proof of bad faith.

So hank's not wrong, scientific hucksters exists. And so do the sincere ones like Dr. Joseph. I find the latter far more interesting than the hucksters, because hucksters just recycle other peoples' ideas far enough to make a buck. At least the folks like Joseph are giving me their own best efforts.