Not a fallacy, in this instance.
Let us assume Walmart sales average $100M per store in a year.
Three stores open in DC, with total annual sales of $300M.
Do you seriously contend that the city’s population suddenly spends $300M more than the previous year for toothpaste and T-shirts? Most, effectively all, of that $300M will come from other stores’ lost business.
You have just expressed a zero-sum fallacy fallacy.
The true zero-sum fallacy is that any one person or organization in the economy gaining business must result in a loss for someone else, that there is only so much wealth to go around.
What I am pointing out is that in any given market, while a zero-sum is not applicable, the total sales are quite inelastic. If McDonalds increases its sales by $10B, it generally means most of that is from reduced sales to other fast food outlets, not that the world suddenly decided to spend $10B on lousy hamburgers.
You assume that, magically, Wal-Mart will price its products at the exact same level as the other retailers.
So, let's say you originally spent $1.50 on toothpaste, and now spend $1.00 (on perhaps a larger tube). And to be fair, let's say you now spend $1.25 on eggs versus $1.00.
Where does your 0.25 savings go? Does it simply evaporate?
1. You are supporting stagnation in the community and are anti-growth and anti-competition. You are also anti-free market. You might want to deny this, but you have now written enough to prove the assertion.
2. You realize that most “mom ‘n pop” stores are over-charging their customers because of their limited buying power or because of simple lack of competition, right? How does this make the community better and why do you confer some kind of moral superiority to them over Wal-Mart?
3. DC government pays an average of $10.50/hour. I don’t get the feeling you have a problem with their hypocrisy in demanding that Wal-Mart pay more? Is the DC government morally corrupt for not paying a subjective “living wage?”