That's probably it. Plus there is an added benefit of a reverse filter. I don't want to work with any company that will, at the least, exchange a couple of emails with me. Any company who disqualifies me from just looking at my CV is not a good fit. Team chemistry for me is very important. I don't want to work in a place full of incompatible personalities. Not fun.
Most of the time filters are "all of", not "any of". A lot of companies may disqualify you if either you lack the necessary skills/talent or if you're a bad cultural fit. Disqualifying based on your CV just saves you time in this case - if they aren't going to hire you anyway, it's better if they let you know quickly rather than drag things out.
