It's not uncommon to send or receive a card at Easter, if fact is a tradition.

The first greeting cards may have been sent by ancient Egyptians who spread good wishes on slips of papyrus. Apparently, Greece and China sent similar correspondence at about the same time. 

Easter cards came about when a stationer in Victorian England added a greeting to a drawing of a rabbit and the became popular in Europe when the postage stamp was introduced in 1840. 

At the turn-of-the-last-century — that would be 1900, not 2000 —Easter cards were often postcards depicting Easter symbols such as bunnies and baskets.

Easter is the fourth most popular holiday for sending cards, ranking behind Christmas, Valentine's Day and Mother's Day.