After searching "algolia" mentioned below, I figured out the misunderstanding. The company was paying somebody else per search made on their web site. So every time a scraper called the website's search function, it cost the website money.
you've misunderstood: the site used something like algolia (which the site paid for) to index. the scrapers were hitting that service (which was costing the site) rather than parsing the xml (which already had everything).