Many Quakers do not celebrate Easter, or indeed other traditional festivals such as Christmas or Lent. The reason is that they consider the resurrection of Jesus as something which should be celebrated all year, rather than just at one season.
The Archbishop of York Dr John Sentamu said that the founder of the Cadbury company would disapprove of the firm removing the word Easter from some of its marketing material because he was a Christian. But it's been pointed out that he was a Quaker and so might not have minded. The company has in any case denied it is removing the name Easter from its materials. And in an additional twist, the word "Easter" comes from a goddess, Ēostre, who was supposedly mentioned by the 8th Century Venerable Bede.