Why does the Town Councillor add "only not quite so useful"?

High above the city, on a tall column, stood the statue of the Happy Prince. He was gilded all over with thin leaves of fine gold, for eyes he had two bright sapphires, and a large red ruby glowed on his sword-hilt.

He was very much admired indeed. “He is as beautiful as a weathercock,” remarked one of the Town Councillors who wished to gain a reputation for having artistic tastes; “only not quite so useful,” he added, fearing lest people should think him unpractical, which he really was not.

“Why can’t you be like the Happy Prince?” asked a sensible mother of her little boy who was crying for the moon. “The Happy Prince never dreams of crying for anything.”

“I am glad there is some one in the world who is quite happy,” muttered a disappointed man as he gazed at the wonderful statue.

“He looks just like an angel,” said the Charity Children as they came out of the cathedral in their bright scarlet cloaks and their clean white pinafores.

“How do you know?” said the Mathematical Master, “you have never seen one.”

“Ah! but we have, in our dreams,” answered the children; and the Mathematical Master frowned and looked very severe, for he did not approve of children dreaming.

One night there flew over the city a little Swallow. His friends had gone away to Egypt six weeks before, but he had stayed behind, for he was in love with the most beautiful Reed. He had met her early in the spring as he was flying down the river after a big yellow moth, and had been so attracted by her slender waist that he had stopped to talk to her.