How? It's 320kbps.
I'm seriously thinking that Google just licensed the audio they're streaming, but they didn't even care about getting proper audio files and they're simply streaming the audio their users uploaded.
In my country there was a big scandal a few years ago when a couple of radio stations started playing Billboard Hot 100 songs. I guess they couldn't source the new songs in time from reputable sources for some reason (licensing restrictions, logistical failure, no idea...).
So they simply downloaded them from local torrent trackers. The thing blew up, because a guy that was uploading and seeding the albums put his own catchy promotional jingle in the middle of most songs.