There is no punishment for you if you send sMerits to your friends. I would like to emphasize that what you send is sMerits (sendable Merits), not Merits. However, you should send them to your friends' qualited-posts, because it is the main reason why merit system been launched, if not please send those sMerits to others in the forum who are deserved.
The merit system was created in order to stop spamming, shitty-posts; and to motivate users to contribute more constructive, higher-qualitied posts over time.
I think that is a member is sending merits to his friend even if he has made a good post, he can be in danger. This will not happen to old trusted new members but for new members, this might be ignored.
It is best to give merits to other people making quality posts. If your friends are making good posts, they will anyway get merits from other members.