Unfortunately it's not just a bunch of kooks like them. Sanders's interview today with with Andrea Mitchell, where he acted like he was the winner and was expecting Hillary to endorse him, will understand that this entire mentality comes straight from the top of the campaign.
I'm going to give Sanders
some more benefit of the doubt. He need to prepeare his supporters and I wouldn't be surprised if he had already coordinating his moved with Clinton and the WH. Though I'd expect him to say something on such crap.