European individualist anarchism tends to be highly influenced by semi-aristocratic libertarian thinkers such as Friedrich Nietzsche and Max Stirner. One of the most important causes that those thinkers are for is individual authenticity and sincerity. So this is why for example Nietzsche has been influential in something like the marxist Frankfurt School.
The Frankfurt School might base its some of its economics in marxism (mainly the critique of the commodity form) but it is not hard to find in it highly individualistic citations relevant to our consumer society such as this:
"The man with leisure has to accept what the culture manufacturers offer him. Kant´s formalism still expected a contribution from the individual, who was thought to relate the varied experiences of the senses to fundamental concepts; but industry robs the individual of his function. Its prime service to the customer is to do his shcematizing for him...There is nothing left for the consumer to classify"
Adorno and Horkheimer. The dialectic of the enlightenment.
"In the culture industry the individual is an illusion not merely because of the standarization of the means of production. He is toletared only so long as his complete identification with the generality is unquestioned."
from Adorno and Horkheimer. The dialectic of the enlightenment.
My thought is that as as commercialism advances, the mediocrity and the homogenizing level grows. Even in small non
capitalist markets such as artisan markets one has the constraint on personality and real emotions that entails having to sell in order to make enough for survival. The famous phrase "the customer is always right" shows this. Now as we enter the capitalist market space the prospective employee has to sell herself/himself, dress a certain way in order to sell an image. At the top of all this we have the marketing technologies who have to learn some form of psychology in order to learn on the art of selling things no matter if they like tsomething or agree with something or not as long as the pay is good.
As such individualism in contemporary cultures has been defended from artistic and bohemian sectors. As far as anarchism specificlly a good essay on these themes is "the soul of man in socialism" by Oscar Wilde http://www.theanarchistlibrary.org/HTML/Oscar_Wilde__The_Soul_of_Man_under_Socialism.html
. In it he puts forward this kind of view:
"With the abolition of private property, then, we shall have true, beautiful, healthy Individualism. Nobody will waste his life in accumulating things, and the symbols for things. One will live. To live is the rarest thing in the world. Most people exist, that is all. "
Italian Individualist insurrectionist Renzo Novatore admired Wilde highly and so went as far as to put him in his personal list of great individuals:
"Individualism is its own end. Minds atrophied by (Herbert) Spencer’s positivism still go on believing that they are individualists without noticing that their venerated teacher is the ultimate anti-individualist, since he is nothing more than a radical monist, and, as such, the passionate lover of unity and the sworn enemy of particularity...But not because he has understood the anti-collectivist, anti-social singularities capable of higher activities of the spirit, of emotion and of heroic and uninhibited strength. He hates the state, but does not penetrate or understand the mysterious, aristocratic, vagabond, rebel individual!
And from this point of view, I don’t know why that flabby charlatan, that failed anthropologist, bloated more and more with the sociology of Darwin, Comte, Spencer and Marx, who has spread filth over the giants of Art and Thought like Nietzsche, Stirner, Ibsen, Wilde, Zola, Huysman, Verlaine, Mallarmé, etc., that charlatan called Max Nordau; I repeat, I cannot explain to myself why he hasn’t also been called an Individualist... since, like Spencer, Nordau also fights the state"
"My Iconoclastic Individualism" http://www.theanarchistlibrary.org/HTML/Renzo_Novatore__My_Iconoclastic_Individualism.html
So it is clear there are strong reasons why individualists have been againts markets and of course their more totalitarian form, capitalism. I think also the situationist International delved in an important way in all of this. In a book of Michel Onfray called "La sculpture de soi : la morale esthétique" (en: the sculpture of oneself) briefly in some part he finds a relationshp with some important aspects of Stirner´philosophy with what the situationist international spoke about.