Originally Posted by
steelreserve
So they can pretend to be smart without actually having anything to say.
Basically the entire point of a lazy rhetorical argument is that the person wants a higher standard of proof than they themselves could ever provide - which is also their way of saying they won't be listening even if you attempt to engage them on that level; they will dismiss any suggestions as wishful thinking, not they they have any better ones.
"In order to prove that I know the most, I will simply shut down all debate. Letting you in advance that I will ignore you! I am right because shut up shut up shut UP!!!"