I've had this very thing happen to me. I was surprised when it happened as it was a first for me. That said, I think it's becoming more commonplace, particular

I've had this very thing happen to me. I was surprised when it happened as it was a first for me. That said, I think it's becoming more commonplace, particular in small to medium size companies who are very sensitive to wasting their own developers' time. If it's becoming accepted practice for companies to dismiss interviewees early, then I see no reason that interviewees should not be able to do the same (politely and professionally, of course)