I see your point SC! Don't get me wrong I love Tony's character and I wouldn't have him play it any other way.
However, Carm has been let down and cheated on so many times by Tony,(even tho, she could/should leave him and not put up with it), she loves him, but always has her guard up and it makes her somewhat "icy" I think.
I think that "salt" incident reminded Tony that he did have a sense of humor and he went home and tried it on Carm. However, I don't think Carm is use to a "playful" Tony. Granted it would have been nice had she responded in a laughing manner, but I think she forgot how to.
TIS