Daughters are never of so much consequence to a father.

Lady Catherine's remark makes one wonder what her father was like.

However, Elizabeth notes the truth of the statement in regards to her own father a bit later in the chapter.

They were hopeless of remedy. Her father, contented with laughing at them, would never exert himself to restrain the wild giddiness of his youngest daughters

His youngest daughters just weren't of enough consequence to make the effort.

When Mr. Bennet wrote to hurry Elizabeth it was because he really did miss her and for the sake of his sanity, IMHO.

"but their father, though very laconic in his expressions of pleasure, was really glad to see them; he had felt their importance in the family circle. The evening conversation, when they were all assembled, had lost much of its animation, and almost all its sense, by the absence of Jane and Elizabeth.." Chapter 12