I don't know what you're talking about: Registration is telling a company you have their product.

Registration of a toaster is sending in a card. Registration of a phone is sometimes done by clicking the eula, sometimes by sending a post card.

Registration of software downloaded over the internet is almost always done by...telling the company you have their product over the internet. Windows still lets you print out something I believe.

I think you missed the definition of registration if you're surprised by the fact information is sent when you register.

That's like being surprised information is sent when you email something.