Because the easiest solution for them is a simple web scraper. If they don't give a shit about ethics, then something that just crawls every page it can find is loads easier for them to set up than a custom implementation to get torrent downloads for wikipedia, making lemmy/mastodon/pixelfed instances for the fediverse, using rss feeds and checking if they have full or only partial articles, implementing proper checks to prevent double (or more) downloading of the same content, etc.