The above is so correct. Ive experienced this firsthand, and after the offer was made I reminded and inquired about my USAFR duty and was later contacted and told that I may not be a fit for the company, a better suited/qualified candidtate was selected instead. In this day and age, its really difficult to prove, especially in a "right to work" state that these practices still continue.

Long gone are the days when a company tells you why you were not selected so you can focus on strengthening that aspect of your interview.