Why didn't Matthew go to William Blair's store to buy the material for the dress Anne of green gables?

Matthew didn't go to William Blair's store to buy the material for Anne's dress because he wanted to surprise her and ensure that she received a beautiful dress that she would love. He chose to go to a different store, where he found a lovely fabric that he thought would delight Anne. Additionally, he was not comfortable with the idea of purchasing fabric from a store where he might be recognized, as he wanted to keep his intentions a secret.