It is a very weighty thing to speak for God. Camping misrepresented God Almighty to billions of people. He claimed that the Bible guaranteed the world would end on May 21st, even though the Bible said no such thing. Even though Jesus Himself said that only the Father knew when that day was, Camping claimed to know better. Camping is a false prophet, not just mistaken, and he led many people astray and has given cause for the world to mock Christianity.
I guess I'm missing the clear distinction between "false prophet," "honestly wrong," and "just plain crazy," or at least the way we, from the outside, can distinguish which one it is.
Teh interwebs are teeming with people who believe "the clocked started" with the establishment of the modern State of Israel, and that everything from today's weather to the 13-year cicadas to the cat digging up my bean patch "proves" that the End is Nigh. Camping just has a radio network, while most don't.