I think the author's Reason #3: Google Just Wants Your Data is on the right track but is such a naive interpretation and limited understanding. I mean seriously. When you literally have referrer and ping data from 90% of modern websites, you can do anything. Fuck not being evil or using it to serve ads, that's a massive amount of data that could be used in any number of their products and services - overtly or not. Yeah, maybe it incorporates into their ad serving algorithm but I doubt it. Google is so much bigger than that.
I don't see any reason for shutting it down because they obviously started it for some reason. I guarantee it wasn't to be nice to designers.