Was this unprofessional?

An interview is supposed to be equally respective on both sides. The interviewer is supposed to be focused on paying attention to the job seeker so as to find qualities in them that would make them suitable for the position and not just relying on resume information, as I believe he was. So to your question, it was not professional.

Yes..He was rude and disrespectful and certainly gives the 'successful' interviewee a reason not to accept the job. If he is like thid during an interview..imagine what he is like to work with. Urgh!

It was highly unprofessional & it was also very rude (on his part), but it's also a sign that it's a laid back workplace (which means you can have a laugh with the co-workers). It happens in my workplace a lot & it's totally laid back.

It was definitely unprofessional. If you'd be working directly with him, I'd turn down the job!

I suppose it could have been a test to see your reaction, but I doubt it.

While it is rude, it's not unusual. I would focus on how you did in the interview and not what the interviewer did.

I would say slightly. But it also depends on the job you were applying for, what exactly was the company/position you were applying for?

I agree with Lex. Do keep in mind that they sometimes do this by design to see how you react.

I think its rude