Today's savvy shoppers love search engines for finding & buying products online. Search for even the most obscure items and search engines will immediately show you thousands or even millions of pages mentioning those items. Scan through the top 50 search results and you're almost certain to find exactly what you were looking for. quite a convenience!
For online merchants, it's not so fabulous. If your store doesn't appear near the top of the search results, those shoppers are very unlikely to ever visit your site. It's a matter of being "lost in the crowd".