Look everyone a living example of an Apple Fanboy.
I think google and Amazon know that the RIAA can not really touch them on how they are currently doing it. Space is cheaper then more than likely what RIAA was demanding in fees. RIAA business model is very out dated and they are still struggling to stay relevant in today's internet world.
Umm, have you seen what the RIAA have done with YouTube? At the absolute minimum they'll insist that Google / Amazon police the service to identify obviously pirated music. Actually, I seem to remember Google Music Beta already having something like that... hang on... http://www.zdnet.com/blog/gadgetreviews/google-music-wont-allow-users-to-store-illegal-songs/24538
Google has a variety of tools at its disposal to identify illegal files. Via a method known as digital music watermarking, record companies can encode files with a variety information, including when and where the song was purchased. If Google Music detects multiple copies of the same information, it can filter the files that contain it, preventing users from uploading the files. Conversely, Google could also be forced by record labels into only accepting music uploads that feature that sort of identifying information.
If the RIAA are smart (yeah yeah, I know, bear with me) they won't touch the services themselves, just use them as a tool to catch and prosecute pirates. A few tests cases and you'll soon see the service die anyway as those who aren't tech-savy enough to strip identification from ripped files realise they're likely to get caught.
And here's the problem Google especially will have: the business model may be outdated but they're not working with the content providers to build a better one, they're trying to enforce something that, basically, only really works for Google. They tried this before with Google TV (actually their attitude towards copyright and IP has historically been rather poor across the board) and, for the first time really, content providers were in a position to stop them. The net result was customers got screwed.
In the long run Apple's approach to this is the right one. Get the content providers on-board and change the system slowly in a way that works for the consumer AND leaves something approaching a viable business model for the provider while transitioning all involved to the new system slowly and as gently as possible. Otherwise you end up with a very, very broken system and a lot of conent creators unable to make a living.