What these stores are doing is offering the exact same product as the larger chains for a 40% markup, and are considerably less convenient to the average consumer.
Again, its
not a markup. Most of the price differential is due to bulk discounts, economies of scale, and in some cases, cross-subsidies with other products- often, they're
selling the product for less than most LGSs' can
purchase them.
In some markets, I wouldn't be surprised if there wasn't even a bit of predatory pricing...but that's tough to prove.
How does that arguement work for Wallmart that does have thousands of storefronts and people?
Wal-Mart generally owns its buildings and the land its on, whereas most LGSs rent their space. That has definite accounting impacts upon the bottom line and profitability.
Wal-Mart operates like a lot of other megabusinesses do. As mentioned above, their size gets them certain economies of scale, and they can demand and get bulk purchase discounts. That, along with the ability to cross-subsidize with other products (with higher profit margins), means that they can often sell a product cheaper than their smaller competitors can acquire it.
Wal-Mart has been through and is also currently under multiple investigations for predatory pricing and unfair labor practices which result in underpayment of employees...which further affects their ability to compete, if true.
Then there are more subtle practices, like exercise of monopsony/oligopsony power.
Like GM and the big auto manufacturers, Wal-Mart is in such a strong position in the economy that they can get those bulk discount purchases on credit...then pay late. When they do so, they often pay less than the amount agreed upon because the small suppliers (with very little economic leverage) have bills of their own to pay, and ANY payment they get helps them avoid going under. There are documented cases (in the auto industry, at least) of large companies paying as little as 30% of the cost of the products they order when things like the time-value of money are factored in.
IOW, big companies get a discount, pay late (sometimes
months late), then pay less than their agreed upon discounted amount, and get away with it because the sellers can't survive without them.
This, like everything else above, further enhances their ability to charge lower than LGS game store prices and still profit.