2006-2007 Signed NRL Tazos, Where Were They From?!

Hey everyone! This is my first post here, I was an avid collector of NRL cards as a child and have recently gotten back into collecting, I have every 2006-2011 NRL tazo which I did get when I was younger, because of getting chip packets from oztag training and such. But tonight I came across these very interesting listings on Ebay:
http://www.ebay.com.au/itm/2007-Nrl...349635?hash=item41c2e03c43:g:S94AAOSwmCVY-u0-
http://www.ebay.com.au/itm/2006-Nrl...399240?hash=item489be93cc8:g:YE0AAOSwuspY-uxF
I immediately started doing research but could only find photos, my general question is, were these cards in chip packets as extremely rare cards or were they won in contests during those years?

Some conjecture on these
Were supposed to be in the packets and some were but there are stories of them being stolen and on sold by an employee
There is only supposed to be 10 of each but slabs of them have shown up in past years