This rule is not specific to Asia. Google does apply the rule that accounts for Google AdSense accounts need to be linked to HubPages accounts which have been active for more than six months in the US too.
The reason is that there were a lot of fraudulent clicks in the early days of CPC advertising. Google now monitor the traffic for the six month period to assess traffic volumes and then more easily detect fraud.
Google is obliged to protect the interest of advertisers and prevent fraud. Do not blame Google blame those who stole from the advertising businesses in the early days of the internet .