Ford did not create a market for his products by overpaying his employees. He created competitors, because he had to charge more to cover cost of the padded wages. As the competition squeezed him on price, he zeroed out product variety and R&D, thereby inviting yet more competition. Shades of what happened to Detroit in the 80's, except the Japanese had a trump card - their cars were not only cheaper and more fuel-efficient; they were more reliable. Without the Plaza Accord that drastically raised the value of the yen against the dollar, Detroit's automakers would be pushing up daisies today.
I wouldn’t argue that Ford “overpaid” his employees. But he did, pre-unionization, pay them a wage that was far above the average of the day and which did permit many to buy the basic and inexpensive Model T they were producing. That the car itself was affordable, in an age when only the very wealthy could think of purchasing an automobile, was far more important than his wage strategy. Being able to attract and hire the very best labor available was probably a far greater motivation than whether or not his employees could buy a car. But the latter was a happy, and one Ford himself touted, end result anyway.