businesses use that tracking to decide whether or not you're committing fraud or not.
"Hey Mr Businessman! I just bought this brand new PC/Tablet/Cell phone and I'd like to buy that really expensive product I saw on your web site. Of course you can't track me. Because I only just turned on this brand new machine this morning."
Do you really think they'll turn you down? Once the credit card has been approved and the transaction completed, I'll just spin up a clean copy of the VM running my browser. And then next week: "Hey Mr Businessman! I just bought this brand new PC/Tablet/Cell phone ..."
On the other hand, my bank does this. It's a good idea in that they can catch unrecognized machines trying to log on as me. And make me step through some additional authentication steps. It's a bad idea because they only recognize one machine per user account. Switch between my office (home) machine and the kitchen laptop and I get the whole third degree interrogation again.