Asked to leave

Went out today to go print out a paper in the computer lab a few blocks away. As usual I passed group after group of people looking at my feet with shocked eyes. I decided to grab a bite to eat at one of the campus dining faculties. I walked in, swiped my card after a pleasant conversation with the card swiper lady and proceeded to grab a salad. Halfway through my meal I noticed a culinary student pass me. I could tell by the look in her eyes she caught a glimpse of my feet. About ten minutes later I was confronted by a manager with a very tall man in tow. I though oh fuck this woman is here to bother me and she brought a bodyguard...She said "Are you wearing..." I cut her off with a quick sharp "No." She told me I cant be in here without shoes. I asked her if there is any law against being barefoot, she aswell as her companion muttered some bullshit about health code and "you cant be in a place that serves-serves food without shoes." I told them I was under the impression that the according to the department of health what I was doing was perfectly legal. Then they shifted their plan of attack and started saying well as a manager she was afraid I would step on something. She had no idea what was on the floor. It was a restaurant selling salads and plastic silverware. There was nothing on the ground. I told them I was leaving and they said no no finish your food and I told them "No, I'm leaving..." Got my stuff and left. Ill be back and if they try to say anything to me again I will show them the documents from the department of health that I am within my right to do this.