No Offense Taken
Ruth said Keith was very gracious and laughed when she realized that he wasn’t lying. He must have found it all quite amusing. After all, being the megastar that he is, it must be seldom that he goes unrecognized and even mistaken for someone down on their luck.
Keith, thankfully, wasn’t offended at all. He was so grateful for Ruth’s kindness that he wanted to do something in return.