The Bee name is rather silly! Oyster is actually "Oyster protocol". The name makes sense when you see how it works. Oyster has two tokens: Pearl "PRL" and Shell "SHL". Shell is used to pay for the running of software, but Pearl is the money making part. What happens is that you embed a script on your website - a single line of copy and pasted html that anyone can do - and it uses a very tiny amount of visitors' CPU/GPU power to mine PRL.
Not wanting to explain this to the public at large (mining is a complicated topic for non-crypto people), Oyster refer to the code as "hunting for pearls" - something everyone can understand. The website owner then gets paid in PRL and no adverts have to be displayed to visitors: a win/win scenario.
Just a little background info for those who are interested.
P.S. Oyster is a great investment right now, it is airdropping SHL on a 1:1 basis for each PRL held on April 6, so price is flying upwards. There is no Shell ICO, this is the only way that Shell is being launched.
RE: Crypto purification