how to turndown interview...

The other day I had an interview with Target for their management training position. I first made the mistake of handing them my resume at the job fair on campus. That set my up for an interview at the career center. I made the appointment to interview with them because in the back of my mind I remember people telling me to take whatever you can get because there are no jobs out there. But I dont know what happened to the workforce now because I am getting hit with job offers left and right! so after I made the appt. the career center won't let you cancel. So i got stuck going to an interview for 90 min at 930AM! I get there and there are like 5 other students there ready to interview. The career center has a separate area for interviews and separate rooms for one on one. They tell me I will have 2 interviews and if the director is not too busy then I might get a 3rd interview....I go through with the 1st one where she basically tells me about the position. I am sitting there saying agreeing to everything she is saying but I really do not think this job is right for me. Working so hard in school for 4 years at a great university I really do not think a career in retail is where my future lays. She tells me the job is m-f and some saturdays and holidays and about a 50+ hr workweek.
YEAH RIGHT?! peace out! I dont want this job. ! working long hours and getting paid minimum salary!
So going into the next interview I just blew it off... I showed no interest in the position. I totally blew the interview that when I answered a question the guy (who by the way was very rude) would arch his brow and be like what?
I leave the room and they say we will go over the answers and see ifyou qualify for the position and then we will get back to you in 7 business days. I sit in the waiting room to see if I am done. and some lady goes into the room i just came out of and says "so how did we do" and shuts the door. She comes back out saying to me "so it looks like the director is busy and will not have time to interview you for a 3rd interview so you can leave". and hands me a suffed target dog. What she was obv. saying was "you do not qualify and therefore you do not go ahead to the next interview." I really should just stopped in the middle of the interview process and turn the offer down. but it was more fun this way to just blow the interview.