Y'know, even if they're not comfortable with something, they have to understand that they need to become comfortable with it eventually. Of course throwing it all in their faces isn't a wise approach, but to become comfortable with something, they need to experience it, little by little.
Besides, I may be speculating a bit far, but them saying "I'm not comfortable with" rather than "don't do" or "you're disowned if you", I think, gives you some freedom in taking the lead, in a way.