This doesn't prevent you from analyzing which sections of your shop or store are frequently visited or how often users buy goods - that can be analyzed using the server logs.

Now, should e.g. Wal-Mart be able to put an RFID tag on you so that they know who you ware the next time you come in? And more importantly, should they be able to contract a third-party, which can then know when you enter any store with which they have a contract?