Lets say a player decides to make 20 something accounts and give all the coins to his main account. That is how it can be abused.
I see. Maybe if they do implement this, have it so that it will check the account age, and if the account is less than x number of days old (lets say 7), it won't allow you to transfer coins. Essentially, if the person creates multiple accounts, they'd have to wait 7 days before they can do what you described, making it less likely (although not eliminating completely) for people to do that. And by the time the 7 days is up, they'll probably have already used the coins you start with, so any that you gift would probably be ones you've actually earned.
An alternative solution, is have a check in place that can see if the coins you are attempting to gift are the starter coins (or newcomer coins or whatever they are called), and if it detects they are, it will reject the gifting attempt