Why does my boyfriends mom and my mom freak out about PDA?

At church if my boyfriend puts his arm around me or hugs me our mom's have a heart attack. There like "NO NOT AT CHURCH" when the other the same age as us can do it and their parents don't say anything. I don't get to see my boyfriend much and they feak out. We can only hold hands and that's it cause everyone freaks out. What should I do ?