Yes! For me, it's because it's easy to assume that the interviewer knows more than me, and is therefore in some sort of position of power.

But I try to rationalise that. Throughout my career, I've worked with people smarter than me. I'm not intimidated by them, so why should I be during an interview?

With that in mind, I assume they know more until proven otherwise. And if they do know more, I treat them the same I would outside of the interview.