Really, is it worth losing sleep over this? Okay it may have been a turgid attempt at humour and if your wife thinks something needs saying, then she should see him an have a chat.
They do make mistakes you know....I went to my godson's confirmation at his school, the officiant, the Bishop of Oxford. He preached about trust and came out with a joke about what trust is. "Take your wife and Labrador and put them in the boot of your car. Leave them there for four hours and then open it and see who is happy."
This, I thought was appalling as did others, a joke yes but advocating domestic violence effectively wasn't 'on'....my mate had a word with the HM and left it that, a quiet word to be passed on that this was inappropriate, an apology being issued.
Your wife should do the same if she feels uncomfortable.