Nabokov's Nonutilitarian Delights

In Vladimir Nabokov's Speak Memory, he writes, regarding his obsession with the somewhat creepy art of butterfly collecting:

Natural selection in the Darwininan sense could not explain the miraculous coincidence of imitative aspect and imitative behaviour nor could one appeal to the theory of "the struggle for life" when a protective device was carried to the point of mimetic subtlety, exuberance and luxury far in excess of a predator's power of appreciation. I discovered in nature the nonutilitarian delights that I sought in art.

Contrast this nonutilitarian delight with a line by Roger Scruton, where in defending the virtues of art he writes of Rembrandt:

The spectator of Rembrandt’s Night Watch learns of the pride of corporations and the benign sadness of civic life.

For an intermingling of reasons I find this about the most depressing line I have read on art, perhaps particularly because it is by someone who is convinced he is defending the citadel of art from the despoilers at the gates. Rembrandt reduced to a petty pedagogue, and this as a statement of his 'validity'. The art experience as utilitarian, as opposed to art working directly on the living structure of the individual self: "The function of art is to provide a spiritual jolt," said Andrei Tarkovsky. One could say there are very fine lines here between the deadness of art as utilitarian worth, and Tarkovsky's higher utilitarianism and the revolutionary refinement of consciousness, but in reality there are immense gulfs of separation in understanding.

On the debit side of Nabokov's nonutilitarian delights is the possibility of the fetishization of 'beauty', as could be argued is his self-confessed obsession with buutterfly collecting, where the living object of one's mania is immediately killed with poison gas and pinned in one's collection.

Another far less noticed fetishization is that of ugliness, of whom Lucian Freud could be said to be a prime example( his famous relation, Sigmund, much loathed by Nabokov). This immersion in the squalid exalted as the highest word in truth and realism. Though again it is merely an abstracting from life of what fits one biased set of aesthetic values.
I'm not sure if it's related here but Sigmund Freud's notion of the self is surely the fetishization of ugliness, where man is reduced to a set of lowest common denominators, with the emhasis very much on 'lowest'.

Perhaps The Picture of Dorian Gray is an awareness of Oscar Wilde's at whatever level of his being of the essentially squalid nature of the fetishization of beauty: the painting acquiring all the imbalances of a life unconcerned with a personal synthesis of life in its fulness, but rather the spiritually immature desire for pure pleasure.