What does anarchy have to do with the middle class? A middle class only thrives in a stable society. Anarchy inherently destabilizes society.  If we want a large and growing middle class we want a stable government. Ideally, one who is supporting those agendas that support family.

Remember, anarchy seeks to flatten things out. Anarchy is the opposite of hierarchy. With anarchy you have no authority figures. This may seem like a great idea but it is not. Anarchy means “without leaders.”
The voluntary association of cooperating groups = anarchy. 

Coincidence? Both anarcho capaitalists and anarcho communists are arriving at a similar stance on various topics. When you go so far right or left you end up backwards in the same position!

Anarchocapitalism is a political philosophy and modern school of anarchist thought that advocates the elimination of centralized state domination in favor of self-ownership, private property and free markets.
~Courtesy of Wikipedia

Anarchocommunism, also referred to as anarchist communismcommunist anarchism, free communism and libertarian communism, is a political philosophy and anarchist school of thought which advocates the abolition of the state, capitalism, wage labor and private property (while retaining respect for personal property, along with collectively-owned items, goods and services) in favor of common ownership of the means of production, direct democracy, and a horizontal network of workers’ councils with production and consumption based on the guiding principle: “From each according to his ability, to each according to his needs”.

~courtesy of Wikipedia

What does the Urantia Book say about private property?

While primitive society was virtually communal, primitive man did not adhere to the modern doctrines of communism. The communism of these early times was not a mere theory or social doctrine; it was a simple and practical automatic adjustment. Communism prevented pauperism and want; begging and prostitution were almost unknown among these ancient tribes.
69:9.2.Primitive communism did not especially level men down, nor did it exalt mediocrity, but it did put a premium on inactivity and idleness, and it did stifle industry and destroy ambition. Communism was indispensable scaffolding in the growth of primitive society, but it gave way to the evolution of a higher social order because it ran counter to four strong human proclivities:
69:9.3.1. The family. Man not only craves to accumulate property; he desires to bequeath his capital goods to his progeny. But in early communal society a man’s capital was either immediately consumed or distributed among the group at his death. There was no inheritance of property—the inheritance tax was one hundred per cent. The later capital-accumulation and property-inheritance mores were a distinct social advance. And this is true notwithstanding the subsequent gross abuses attendant upon the misuse of capital.
69:9.4.2. Religious tendencies. Primitive man also wanted to save up property as a nucleus for starting life in the next existence. This motive explains why it was so long the custom to bury a man’s personal belongings with him. The ancients believed that only the rich survived death with any immediate pleasure and dignity. The teachers of revealed religion, more especially the Christian teachers, were the first to proclaim that the poor could have salvation on equal terms with the rich.
69:9.5.3. The desire for liberty and leisure. In the earlier days of social evolution the apportionment of individual earnings among the group was virtually a form of slavery; the worker was made slave to the idler. This was the suicidal weakness of communism: The improvident habitually lived off the thrifty. Even in modern times the improvident depend on the state (thrifty taxpayers) to take care of them. Those who have no capital still expect those who have to feed them.
69:9.6.4. The urge for security and power. Communism was finally destroyed by the deceptive practices of progressive and successful individuals who resorted to diverse subterfuges in an effort to escape enslavement to the shiftless idlers of their tribes. But at first all hoarding was secret; primitive insecurity prevented the outward accumulation of capital. And even at a later time it was most dangerous to amass too much wealth; the king would be sure to trump up some charge for confiscating a rich man’s property, and when a wealthy man died, the funeral was held up until the family donated a large sum to public welfare or to the king, an inheritance tax.

One of the most important things that lead to a high type of civilization is private property.

Consider:

The red men were too democratic; they had a good government, but it failed. Eventually they would have evolved a state had they not prematurely encountered the more advanced civilization of the white man, who was pursuing the governmental methods of the Greeks and the Romans.” 71:1.12

This included the concept of private property.

The Evolution of Government

70:0.1.NO SOONER had man partially solved the problem of making a living than he was confronted with the task of regulating human contacts. The development of industry demanded law, order, and social adjustment; private property necessitated government.
70:0.2.On an evolutionary world, antagonisms are natural; peace is secured only by some sort of social regulative system. Social regulation is inseparable from social organization; association implies some controlling authority. Government compels the co-ordination of the antagonisms of the tribes, clans, families, and individuals.
70:0.3.Government is an unconscious development; it evolves by trial and error. It does have survival value; therefore it becomes traditional. Anarchy augmented misery; therefore government, comparative law and order, slowly emerged or is emerging. The coercive demands of the struggle for existence literally drove the human race along the progressive road to civilization.

Check out the Urantia Book for more information about anarchy, communism, private property, and so much more.
www.urantiabook.org