What you say is true, however I think despite there being levels of salaries/pay that are excessive for some employees and studies that indicate that there are better motivators than salary/pay, from what I'd read, Walmart had not been paying employees adequately or giving them adequate training, so anyone who dismissed what they did as "wrong" I think is misinterpreting arguments for high pay as "paying employees more is always right" vs. "in some cases, employers could be providing a better customer experience and encouraging sales and growth longer-term by paying their employees more."

Also, please read:

http://www.keithrull.com/blog/wp-content/uploads/2013/01/net...

While it's not always applicable, paying more for the best is not a bad idea in dev and IT. Just be sure that you can survive up to 100% of the top people on your dev and IT teams getting replaced by ensuring you have good design, good code, good management, good training, and good documentation.