You're conflating crawling with querying/ranking in a weird way. And: grep - are you serious?
(Yes, you also namedropped Pagerank for some odd reason.)
The thing is, though: You can't easily outsource the crawling and then do the quering/ranking inhouse. The reverse index and various other data structures you need are inherently tied to the data structures from the crawler output. This is a very large amount of data and it's changing often.
The outsourcing that is being done is at the "search query to results" level. That is why this is so disappointing.