"interviewer could probably think that it is he who will have to pay you for the time spent chatting." Well, if you're planning on spending some of your time a

"interviewer could probably think that it is he who will have to pay you for the time spent chatting." Well, if you're planning on spending some of your time at work arguing about Lisp online anyway, why hide that from your employer? Either they're OK with it and it doesn't matter, or they won't like it and you probably wouldn't want to work there anyway.