Final answer:
McCann and Morrison pass along Quitters Inc business cards to recommend the service to others who are struggling to quit smoking.
Step-by-step explanation:
McCann and Morrison pass along Quitters Inc business cards because they are both smokers who have successfully quit smoking with the help of Quitters Inc. They pass along the business cards as a way to recommend the service to others who are struggling to quit smoking. By doing so, they hope to help others achieve the same success they have experienced.