Fame
No way. A greeting card writer deliberately writes in a "me-to-you" voice (source). Through the card, the card sender (me) speaks to the card receiver (you). As for the greeting card writer, a.k.a. anonymous, shadowy, Batman-like figure in the middle of this transaction?
No one wants to know who you are. They just want you to do all the work for them, as quietly as possible. Unless you craft the next Great American Novel and cite your time as a lowly greeting card writer as your "formative years," no one will ever know what you do.