That's what I logged in to ask... what's the point of a scheme like this when blocking exists?
A couple of years ago I ordered a iPhone & case from T-Mobile, and one day a signature required box showed up with just the case in site. Upon investigation by T-Mobile & FedEx, it was found the box was light from the original warehouse, so someone must have screwed up and not put the phone in the box... but had scanned it as linked to my account. Fast forward a couple of weeks and I get an email noting that the IMEI of that phone had been permanently blocked and would not be activatable.
Sure, maybe some random carrier in far away country doesn't check those lists... but wouldn't Apple also block such a device?