I agree that it is not your place to say anything. You will be considered an interloper and it will only cause more problems. It's hubby's place to handle it. If he doesn't, you simply let it go. I don't mean you put up with anything, you simply distance yourself and hand the phone to hubby every time one of them calls. I don't mess with his family and he doesn't mess with mine. My family thinks he farts butterflies because he doesn't argue with them.
Your hubby may need this explained to him. Some men simply don't "see" what is happening or that it is abnormal because that's the only way he's ever seen his family act. If he disagrees with your perception or agrees and still doesn't say anything to them, it's out of your hands. Grieve the loss of your dream of how it would be and move on.