So many people have such weird concepts about dog training! The first time someone grabbed my dog's tongue would be the last!
Gracie also likes to lick. She knows that she gets three or four licks with me and then that is enough and that is what I tell her, "that is enough." She knows to stop. I find it strange that people don't just teach their pets the word "no" or "no more." Dogs can understand such words if the owner is consistent.
If someone comes to the house that does not know to tell Gracie "no" then I just tell them that they need to tell her "that is enough." When they say it she stops. Much less painful than having the tongue pulled.