Answer: Useful, because religions affect attitudes and beliefs across cultures.
Step-by-step explanation:
The knowledge of religions and their associated practices is important for marketing and sales of products at the national and international levels. As if a person belongs to different country or religion will require to practice own religion or celebrate own festival. This is beneficial for the people in the market selling those religion oriented products and services.
Thus this can be considered that the religious believes may affect the attitudes and believes of people of different cultures as well.