Wasting public funds

Everyone wishes to greet relatives and friends on special occasions during the year. Ideally, one would like to meet the person to greet him. Since this is not always possible, we take the help of greeting cards. To meet the demands, greeting cards are manufactured and sold. When you send a card to greet a friend or a relative, you expect it to be reciprocated.
As a teacher in a university, I receive several dozens of greeting cards every year from such persons as the Honourable President of the country, the Vice Chancellors and Pro-Vice Chancellors of a good number of universities and Deans of the various Faculties of my University. These personalities presumably use public funds to procure the greeting cards. I have to spend money from my own pocket if I have to reciprocate. I must admit I have never reciprocated. I don't think I would, even if were very rich because I believe they would not have the time even to look at the card sent by me. I wonder some times if I would do the same if I were in their positions. What would be the purpose ? I can't believe they send a card to me because they remember me. I am sure some of them don't know me even. Similarly, I don't know some of them at all. May be they want to declare to persons like me that they are holding a high office, which we have not been able to hold. What do I do with the cards ? I find it difficult to accept it as a greeting.
I would humbly like to tell these personalities that they are wasting public funds, which could be definitely put to better use.