I'm with you. The comments diverged towards debating that particular case: "I think he was rude"/"we can't tell if he was…", but the point you're making is about the more general question: excusing yourself from further interviews is not necessarily burning bridges.
"I'm sorry but I don't think it's worth both of our times to continue. I just don't think I'd be a good fit here. It's nothing wrong with you or me, it's just that we don't have the same vision on some things. I really appreciate the opportunity, etc."
If the guy had three hours of interviews already and 3-4 more in the afternoon were planned, plus a lunch, I don't see the problem. It's very easy to end up doing interviews and realizing that the position is not what you had in mind: maybe there's more travel, less hands-on, you'd be working by yourself on the project, etc. You can often easily tell that's not what you're looking for.
Of course, I wouldn't leave in the middle of an hour-long interview and I wouldn't give the impression that I'm rushing out either.
"I'm sorry but I don't think it's worth both of our times to continue. I just don't think I'd be a good fit here. It's nothing wrong with you or me, it's just that we don't have the same vision on some things. I really appreciate the opportunity, etc."
If the guy had three hours of interviews already and 3-4 more in the afternoon were planned, plus a lunch, I don't see the problem. It's very easy to end up doing interviews and realizing that the position is not what you had in mind: maybe there's more travel, less hands-on, you'd be working by yourself on the project, etc. You can often easily tell that's not what you're looking for.
Of course, I wouldn't leave in the middle of an hour-long interview and I wouldn't give the impression that I'm rushing out either.