And there is no ACH facility offered by Indian Bank accounts. So the money transfer is just one way. From Paypal --> merchant's bank account
What do you mean by that. What is an ACH facility?
Anyway great post and way more useful than talking about power consumption and ROI of vaporware

ACH facility means. If a merchant has USA paypal account and link their bank account with Paypal / provide them authorization.
That means, in the event that a user files a dispute or requests refund, then paypal can withdraw money from the bank account.
ACH facility is a two way fund transfer.
Something on those lines. But with Indian bank accounts, that is not possible.
P.S : Someone correct me if am wrong.