Your lemonade stand would be more like if there was a stand on every block: By virtue of the scale of their business they could afford to undercut any competition that tried to start up. If they did that they could be slapped on the wrist for being anti-competitive.
Walmart has been accused of selling merchandise at such low costs that competitors have tried to sue for predatory pricing (intentionally selling a product at low cost in order to drive competitors out of the market).
In 2000, the Wisconsin Department of Agriculture, Trade, and Consumer Protection accused Walmart of selling butter, milk, laundry detergent, and other staple goods at low cost, with the intention of forcing competitors out of business and gaining a monopoly in local markets.
Crest Foods filed a similar lawsuit in Oklahoma, accusing Walmart of predatory pricing on several of its products, in an effort to drive Crest Foods’s own company-owned store in Edmond, Oklahoma, out of business.
However, in 2003, Germany’s High Court ruled that Walmart’s low cost pricing strategy “undermined competition” and ordered Walmart and two other supermarkets to raise their prices. Walmart won appeal of the ruling, then the German Supreme Court overturned the appeal.
Walmart has been accused of using monopoly power to force its suppliers into self-defeating practices. In 2006, Barry C. Lynn, a senior fellow at the New America Foundation (a think tank), said that Walmart’s constant demand for lower prices caused Kraft Foods to “shut down thirty-nine plants, to let go [of] 13,500 workers, and to eliminate a quarter of its products.”
Cough Walmart cough