Car guards at centre

The car guards at this centre should be thrown out... This is the second time this has happened to me and the fourth time I have heard from someone that it has happened to them... I arrived at the centre and was approached by one of the car guards. I responded "No thank you, my car will be fine".once I had finished my shopping and returned to my car, a car guard followed me to which point I said "No thank you I will load my own car and take the trolley back myself". Once I had done this and was leaving he then insisted showing me to reverse after I had said I can do it myself twice. Once I had reversed he came to my window looking for money and I shook my head no. He then started swearing at me to which I climbed out of my car and asked him what his problem was. He then threatned me physically and started to call the other guards... Escilating I finally said to them if they wanted to physically attack me I would defend myself. One of the guards went towards my car to kick it and I pushed him away. I want to know when will something be done about these guards not only here but at many other centres? This is getting ridiculas.