Looks like it is an (awful) new policy, as I just received this in an email.
Such a small pleasure, to be able to remove the ads and put a couple of new books on in time for his birthday (without opening the package), gone.
I suppose it’s a piracy thing? Could it be in direct response to a post on here about trying to change a serial number? No, that is paranoia.
Still, it’s the end of a little era.