Answer:
No, it is not a correct attitude, since what they said could be a lot worse than they thought, and if you say it to a certain person, it could really be rude. If you correct them, or tell them that what they said is rude, they would realise it and not say it again. If they dont care that it is rude, or if they get made at you for telling them, they arn't thinking correctly and you should just let them think about it. They will realise what they said/did was wrong, and they wont be mad at you anymore. :)