I wouldn't call a smack "hitting children". There seems to be a touch of the moral highground going on in this discussion.
For me a quick smack is kinder than the naughty step, removal of privileges or reasoning with them etc. None of the children in my family have suffered from a smack, and none of them need one now. All it takes is a "look" over glasses perched on the end of the nose.
We might be an old fashioned family but all the children know how to behave which is more than I can say for some whose parents "reason" with their badly behaved little snowflakes and get ignored.
However, I would not dictate or suggest to anyone who disapproves of a smack as being wrong. They have their way, and we have ours.
Charity Shops Making Donations Uncomfortable

sounds like you deserve a holiday.
