Why, pray tell, would one not wish to register with Apple? Without registering, at least a new system, you will not get Apple Support. Also, it is not as though Apple solicits you via phone for anything, nor do they abuse your e-mail. The only e-mails I receive from Apple are information about hardware upgrades, and it takes less than 7 seconds to remove myself from the email list, however I don't because I actually like getting the email.
Register, don't be an idiot.
TEG