I had the pleasure of chatting with Crucial today.
You see, once upon a time their consumer drives of yesteryear offered a free Adobe Creative Cloud license for 1 month. SO what happened is people would buy their drives from Amazon, redeem the 1 month free license online by registering the SN, then return said drives to Amazon.
Crucial caught on to this, and "temporarily" (forever) stopped online product registrations.
So now, live chat to say "hey, how do I get my code?" and you get a code.