Unprofessional Interviewer

I got a referral for the sales position from a friend who has worked there for a few years. I applied online and within a week or two i got a call from a recruiter. She asked if I had time to answer a few questions and I said yes. She asked a few personality and general interview questions and more specifically, why I would like to work for the company. The conversation lasted around 15 minutes and afterward, she asked to set up a day/time for a more intensive second phone interview and gave me information to take an online personality/traits test in the meantime. The second phone interview was much of the same. General interview questions coupled with a few behavioral/star questions. After the second phone interview they called me back a week later with a formal interview request which I gladly accepted. The offices in Sartell MN where I interviewed were nice, clean and the employees were nice. Many long rows of computer stations with people working at them, with offices in the rear. My interview was a 3:1 process. Three upper managers, whom were very laid back, welcoming and nice, peppered me with questions, many of which were behavioral based. They aren't too difficult, just make sure to give good real life examples if you can. Lastly, they asked me an industry specific question, that they admitted nobody ever really gets correct, but want to see your thought process through to your answer. It dealt with how to re-route carrier trucks in the same region when one or more is having mechanical issues. I guess I must've got the question completely wrong because I got a call 2 weeks later saying the interview process was a positive one, but they decided to hire internally instead.....giving me no other information.