Usually, they are stumbling all over themselves, and completely failing every question they are asked. These become the sorts of interviews people write about on The Daily WTF and other blogs online.

That is, unless they interview at an organization that is much more interested in finding compatible personality for their culture than they are in the person's ability. These organizations exist; I worked for one a year or two back. The candidate I was interviewing as part of a panel had not been asked a coding question to that point, and she was already quite far along in the interview process -- the next step after the panel interview was an offer. No one else really cared; they just wanted someone who would increase headcount while not disrupting the culture and structure of the organization.

So, the people who answer this way, they're just playing a numbers game. They keep going on interviews until they hit an organization like I describe above; at that point, all they need to be hired is to just be agreeable.