Of all the ways in which the advancement of free markets in the age of industrialization changed society, its effects on the arts may be the least obvious.
After all, the images most connected with the tumultuous second half of the Nineteenth Century are those of factories, smokestacks, and violent labor strikes, not the placid fields of wheat, gardens of water lilies, and bridges across glittering streams that are what most people associate with Impressionists, a group of artists that appeared at this time.
But clichés aside, the work of famous impressionists like Claude Monet, Pierre Auguste Renoir, Camille Pissarro, and Alfred Sisley was made possible by a host of interlocking economic and social changes brought about by the effects of industrialization and the numerous advances caused by the spread of free markets within western countries.

Innovation in Markets Leads to Innovation in All Aspects of Society

The tremendous expansion of the middle class that came along with industrialization was crucial in stimulating a new market for art.  The trappings of luxury that in prior centuries were limited to the extremely wealthy became more affordable, just as there were more consumers who sought to decorate their homes in ways that signaled their social level.
As wealth spread more throughout society it changed the old concepts of patronage through which artists had previously made their living.  No longer were painters forced to shape their art to comport with the tastes and expectations of a small group of princes, kings, and archbishops who commissioned portraits and ceremonial paintings.
While most of the upper classes still drifted in the sway of accepted styles and forms, their tastes more in line with the tastes of the official academy, an impressionist could follow his muse and paint whatever he chose, relying on a new crop of dealers who would seek to match these new works with new consumers.
When the Impressionists were excluded from shows and exhibits put on by the established salons and academies, they began staging their own independent exhibits starting in 1874.  It is axiomatic among those who study it (Milton Friedman, for one) that free markets and free thought go hand in hand; economic freedom and personal freedom are two sides of the same coin.
Within an increasingly free society, painters who wanted to paint in different ways flourished.

Mass Production and The Lasting Impression it Made

On a practical level, the proliferation of mass production of everything from paint to brushes to canvas allowed for a level of experimentation that the Impressionists embraced with abandon.
Productivity and the attendant falling cost of supplies made failure affordable—a landscape that didn’t quite capture the light the way the artist wanted, or a palette of colors that didn’t blend as anticipated no longer represented as much an investment lost as before.  Quicker more impulsive techniques of painting caught on rapidly as the Impressionists tried to capture a fleeting moment or (as their name implies) an impression more than accurate and detailed representation.

Impressionists were greatly aided by numerous technical innovations that were inextricable from advances in manufacturing.  The resealable metal paint tube, for example, was invented in 1841 and by the 1860s was being mass produced.  It revolutionized the way painters dealt with their primary material.
No longer did paints have to be mixed by hand right before their use, and now small amounts of more colors could be squeezed out onto a pallete whenever the artist’s eye determined a particular hue was necessary.  A tray of small paint tubes revolutionized the act of painting outside the studio whether out in the countryside or in a city park.
Artists understood the liberation that this gave them.  “Without tubes of paint,” said Renoir bluntly, “there would have been no impressionism.”
An increasingly open society—open to new ideas in every field from business to religion—was of fundamental importance to the Impressionists, and indeed to all the artists who were inspired by the new Modernist determination to make art in a different way.  Similarly, the productive capacity of a vital and industrializing Western Europe was a liberating force for skilled painters who sought, along with the rapidly changing times, to forge new styles of painting.
The emergence of the Impressionists was not just a momentous element in the history of painting, it was also a testament to how the developing industrial economy and a maturing free market were already shaping arts and culture.