I caught clip of James O Brien talking to a reform voter. He disproved the assertions made by the caller on air, but finished by asking the caller what was motivating them to immediately go back to spouting what they now knew was bollocks when they hang up. Which is basically accepting that for some people facts are immaterial. If they support your views then fine. But if they don't, just pretend they do.
I had a similar experience a few years ago. A colleague was upset that there were so many Polish people in the UK after they were against us in WW2. A quick history lesson with pictures (so as not to confuse) and they accepted they were wrong.
A couple of days later I heard them repeating the same bollocks thinking I was out of earshot.