Including other cultures and their respective norms in your story provides additional texture. Just make sure you get it correct, either through research or, better yet, consulting with someone who knows it well.
One of the best examples I’ve seen where this is done beautifully is the movie “My Big Fat Greek Wedding.” You may be part of such a culture and not even be aware of it.
Many years ago when I worked for NASA I attended a class that addressed getting along with people from other cultures. This was essential because we were working with Japan, Russia, Italy, and various other countries with the International Space Station. One thing they told us that I’ve never forgotten is that right and wrong can have entirely different definitions in different cultures. They are what they are, having evolved separately and under different circumstances.
Cultural microcosms are all around you, whether you notice them or not. If you’re an author, you should pay attention to such things. Every city, even section of a city, has its own personality and culture. This is perhaps more noticeable among the different states of the USA and certainly between other nations. Cultural clashes surround you on any given day. If you don’t believe me, just watch the news. Remember that conflict is essential in fiction and this is another area where you can work it into your story.
Pay attention to such things as an essential ingredient to life and therefore has a bearing on fiction. Capture it properly and you can become an outstanding author.