As far as I can tell, Marr was asking Farage about his record and things he has said in the past. It would be pretty crappy journalism to just let an interviewee dominate the conversation with their preferred subject.
Farage's past statements are, like it or not, part of what you are voting for if you vote for his party - because he basically is his party. The leaflet has a huge picture of his face and no policies of any substance. So his record is relevant, whether he likes it or not.