Rich snippets plays an important role in search engine optimization (SEO), It’s not direct effect in a ranking signal but it’s benefit in the indirect way in SEO.
Using structure data (schema markup) into your website HTML code, you can give the more information to Google about your content, it’s helped the Google crawler to better understand about your website content. When any user enters any search query, Google try to understand the intent of searchers then provide the most relevant results for this query.
Rich snippets can include more additional information about your business hours, location, product availability, pricing information, ratings of any product and can show the reviews of users related to product.