The forum has been hacked a couple of times in the past, including once in which IP information and email addresses were leaked. Do you want the possibility that your KYC documents are made public?
Good point. I also hope for those of us who have provided KYC information, that this information is stored offline.
I believe that information was collected to allow theymos to generate 1099s for payments sent. There isnt any reason to keep this online and certainly no reason to keep it on public facing forum servers.