I think you are confusing anonymity with something else. Bitcoin is entirely anonymous, but all transactions are public. You can create as many wallets and keys as you want, and you don't have to tell anyone you own them.
[1] http://yro.slashdot.org/story/14/11/26/2121214/bitcoin-is-no...
And it's damn hard to buy a yacht anonymously regardless of the unit of account the transaction is done with.
It's not anonymous, but certainly more private than using a debit or credit card!
In practice, people don't care, because they aren't doing anything illegal.