wearing a cross

Q: If one sees someone wearing a cloth or shoe with a cross sign on it and one does not tell him this is haraam and kufr to wear, does one fall in kufr?

Q: What does emulating the kuffaar mean? Is it only confined to clothing or does it also relate to other aspects of one's life? We see the kuffaar driving cars and eating and drinking in plates and cups and we Muslims also do the same. Is this not also emulating the kuffaar in our actions?