Google won't really ever buy a script and implement. They would want to write it themselves. They also like to encourage developers to write scripts, because it adds capabilities to SU, and makes SU even more popular. Soo, it doesn't make a lot of sense for Google to implement things that others have already made, because its not cool to say 'hey, develop scripts', then turn around and re-write them to distribute with SketchUp, and not pay the author. So its not really a good business model for them to follow the way they currently run things.
But even still, we had booltools before they released their solid tools. Making a terrain from 3d points was a script before the sandbox tool were added in version 5. Like Alan said, 3dtext was a plugin first, then SU wrote it. So they have done it a few times, though I'm not sure they really did it on purpose per se.