Is it normal for my husband and his parents to discipline me?

I understood that when I married my husband we were in a domestic discipline relationship and I would be disciplined for bad behavior. Most of the time everything works out very copacetically, however recently I have started receiving discipline from his mother and father. Family events, holidays vacations, even just weekend dinners at their house. It started out when my husband spanked me for acting bratty at a family dinner, he said my behavior was so out of control that he could not wait until we got home or we're in private. His mother his father, his sister, and her husband all witnessed him do this. Ever since then I have been disciplined by both his mother and father a number of times, both in private and in public. Is this normal? I was used to my husband disciplining me but his mom and dad!????