My mother always taught us it was 'common' to eat in the street and we were never allowed to have chewing gum. Once I disobeyed her and bought a penny chew when I was out with my friends - it was pink and tasted really sweet. They could all blow enormous bubbles, but when I eventually managed to blow a big bubble it burst and got stuck in my long hair. I still remember the telling off I had when I got home and it took ages to get it all out. It sort of put me off.
Nowadays I don't like people who chew noisily with their mouth open; neither do I like the way some people dispose of the finished bits of gum - on the floor, under seats etc. UGH!