[ars]

I registered years ago, I can't even remember how long ago (5 years+ I'd guess, maybe even 10). I have not gotten a single email from them.

I don't understand why they want the registration, but at the same time it's not problem to do it.

[timwiseman]

I am speculating here, but I suspect it gives them a metric that is in some ways more reliable than just measuring unique IP addresses.

Most likely it is that metric they really want, but if you want to be cynical, they could be selling those addresses without ever sending a single message themselves.

[ars]

It's a unique email address that no one else has. It has never received email.

[wglb]

I get mail from them but it is really quite infrequent. Perhaps it ends up in your spam folder?

[igrekel]

Sorry for the stupid suggestion but Have you checked in your spam box?