The FBOs should be harangued by their customers for even letting the screeners onto their property - they need to grow a set (of brains too). I'm almost tempted to call up the FBO and do a little haranguing myself.

However, it was the private pilots and passengers who let this happen to them - they could have flipped the screeners the bird, went on their way and departed and there would be nothing the screeners, nor TSA management could have done to stop them. If the screening was a violation of policy, they can't be fined for refusing it.