Did you catch that? The guest wants everyone to have their own tank. Ridiculous. That's a straw-man argument...
So, why do people agree to be interviewed on his show? He simply preaches to his choir while the guest sits by chastised by Piers' superior intellect and moral position. Even if the interviewee wins the debate, his audience still agrees with Piers. That's why they watch him.
Which brings me to the more important question: Why do I waste my time talking about him? I'm only expanding his audience. Fortunately, the number of people who watch his show is ridiculously small. Most episodes draw fewer than 100,000 viewers which hardly registers on anyone's poll.
I suppose that we are drawn to Piers for the same reason that we watch a parade of American Nazis. We are assured that all is right with the world when we are reminded just how few are drawn to radical causes. So, keep it up Piers. Your failure makes me smile.