In a recent article by the New Yorker it tries to make the case that big business is better for the economy then small business:
Can Small Businesses Make America Prosperous? : The New Yorker

One historical example they give to try to justify this position is as follows:

"The Robinson-Patman Act, of 1936, effectively made it illegal for suppliers to offer chain stores better deals than they offered other retailers. And state and federal fair-trade laws allowed manufacturers to set a minimum resale price for their goods and to legally prohibit retailers from discounting them.

The odd thing is that although these laws stemmed from a populist movement, they actually resulted in price increases for the public at large. "

However, if consumers only save money through gouging manufactures then manufactures will have less money to pay consumers wages. Consequently just because chain stores save consumers money it does not mean that they provide a net good to the economy. I will grant that their can be some economies of scales. For instance, you need enough customers to keep your cashiers busy but at some point this cost savings becomes negligable and all aditionaly growth creates unnecessary overhead.

Early on, the marginal value of this complexity is positive—each additional bit of complexity more than pays for itself in improved output—but over time, the law of diminishing returns reduces the marginal value, until it disappears completely. At this point, any additional complexity is pure cost.

Tainter’s thesis is that when society’s elite members add one layer of bureaucracy or demand one tribute too many, they end up extracting all the value from their environment it is possible to extract and then some.
The Collapse of Complex Business Models Clay Shirky

Of course the whole point of the article is a bit of a red herring because even if large business often does better it do not mean that there should have unfair advantages to protect big business.