I send gifts to people and they don't gift me back, but I don't think there is anything wrong with it. I want to give them a gift because I appreciate them, don't gift them so they gift me or it seems you're only giving to recieving instead of giving because you truely want to give. IMO once you start giving people stuff expecting something in return then you truely aren't doing it for the giving part anymore.

Just my opinion though. Also I like to write notes because cards are everywhere, a hand written note with your feelings is much better IMO.