I never had children, but I was a child. My parents believed in spanking, but I never remember (1) being struck by them in public - or - (2) being emotionally scarred by being spanked. Then as I got older, the spankings turned to lectures. I remember when I was nine saying to my mom (who was lecturing me at the time) "Mom, can't you just spank me and get this over with?"
I have worked with a lot of kids over the years and discovered that every child's personality is different, and they react to different forms of punishment. Unless I see someone very inappropriately disciplining their child in public, I stay out of it. To me, a spanking done in anger is always inappropriate. The punishment should always fit the crime.