What does it mean when a man offers to walk a woman to her car?

The situation takes place in a night course. He happen to see me at my car one afternoon, so he knew where I was parked. That night after class we were talking about the following week. I ended the conversation and said "Bye". He goes, " Hey do you need someone to walk you to your car?" I paused for a sec and he said, "You're parked in the back right?". I said I was, and he said if I waited for a min.(he had to walk to the other end of the building to go to his office) he would walk me. I walked with him to his office then we went to the parking lot. It is also important to mention that the location of my car was not dangerous at all. In fact my initial reaction was to say "No, I am fine". In conclusion, was he just being polite,(btw, he is a real smart ass) or was there more to him offering to walk me to my car?