I totally respect that position. When I spanked my kids (think I only had to spank the older one once and the middle twice), it was before they learned respect and what the right thing to do is. You make it sound like parents spank kids for every rule infraction. I can't speak for any one else, but that's not the case with us. It was the "nuclear" option... when other punishments either weren't working or would take too long to sink in.
I think you’re being generous based on your limited spanking if your kids (so you want to hope that’s how others are also using it). In my experience, most people who advocate for “all kids need a butt-whooping” are spanking their kids a lot more than once or twice in their lifetime. Just because you chose to use corporal punishment very sparingly does not make it the norm. I have seen relatives, friends, and strangers smack their kids all the time, typically over very minor infractions like being annoying, not sitting up straight, not paying attention, talking back, etc.
Many parents who recommend spanking think it’s a normal go-to response for anything their kid does wrong. Heck, there are even multiple parenting books and methods that advocate regularly smacking babies and toddlers starting at 6-12 months to teach and correct, so there are certainly people who think frequent spanking is fine.
Im sure you can find plenty of statistics, but here’s an excerpt from a small study I just saw about how often kids are spanked based on study participants who used audio to monitor frequency:
“The rate of corporal punishment, such as spanking and slapping, exceeded estimates found in other studies that relied on parents reporting their behavior. While other studies discovered that American parents of 2-year-olds typically reported they spanked or slapped their child 18 times a year, Holden's research based on the audiotapes discovered such behavior occurred 18 times a week.”
Even if the self-reported figures were accurate, that’s still once or twice per month, not once or twice in a lifetime like you mentioned.
ETA: I’m definitely not doubting anyone in this thread about how often they spanked their kids. Just that I think frequent spanking is much more common than once or twice as a last resort for something serious.