Sure, but Google also cares about not letting third parties manipulate its search results.
Yes, but to what extent? If they're only concerned to the extent that it doesn't wreck their results, having one site get screwed over is not likely to harm their advertisers or visitors.
Google must realize that everyone and his dog knows how to manipulate links by now, but they've only come up with new and more disastrous ways to count them in the algo. They may be "concerned", but if they were REALLY concerned, they'd remove links or just "not count" the bad ones, as we've all discussed.