It's Okay to Walk Out of an Interview
Recently, I was in a conversation where the person I was speaking with asked me about a former position I held and she said "Why did they hire you?" I was pretty taken aback by the question, I said "Pardon me ?" And she again said, "Why did they hire you?" I thought to myself, "Wow... who the hell frames a question that way?" There were plenty of other indicators that I was in a completely wrong conversation so I didn't bother to go there in the dialog. I figured I'd save my breath for someone more worthy to speak with, and I quickly found my exit strategy which essentially was "I don't think I do what you need."
Whether the conversation is with a potential client, employee, employer, vendor, or even a potential friend... when the direction of the conversation pokes at your integrity and values, simply find a way to exit - naming it or not. Either way, don't bother hanging around. The relationship will mimic what you see and feel in the first encounter and will be unsatisfying at best and an unfortunate distraction costing time, money, and exasperation at worst.
When I was in graduate school, the emphasis put on "contracting" was enormous. I continue to use and share that teaching regularly. Whatever the dynamic is during "contracting," (e.g. those initiatial conversations before signing the dotted line to officially be in a relationship with someone) will play out during the engagement. We have to listen to the cues and make choices about whether the things we see during those initial contracting conversations are (1) deal breakers or (2) doable.
Our guts tell us pretty quickly. If you find yourself rationalizing, heed the warning. It is never a good entree and more than likely will be a burdensome relationship/dynamic. Always be willing to walk away (and quickly). There are plenty of potential clients, vendors, employees, employers who share your same values and have similar integrity. Don't waste much time with those who don't.
Here is a good article from Liz Ryan on feeling free to walk out of an interview - and that can be as the interviewer or the interviewee.