Circa 1973, the front lawn of my high school was like a mini-Woodstock most days.
One day, a big fight started, and police were called to quickly put a stop to it. There was some hands on wrasslin involved.
In any case, as I left school that day, I walked across the lawn where the fight was, and spotted nickel cartridges in the grass...
Six Remington 148gn wadcutters which fell out of an officers dump pouch.
So, some departments did use them, I guess.