Why are you shopping at Wal-Mart?
http://wakeupwalmart.com/facts/
Did you ask a customer service manager to "count down" the machine? These machines are being removed not replaced during store remodels...You may have had a valid concern - ask to speak with the store manager... If he/she does not take care of the problem to your satisfaction contact the district manager then the corporate office.
Oh I have included a link to some Wal-Mart facts for you to consider when answering the question posed to you.
Here are some interesting facts concerning poverty (not that it matters to you - or you would shop elsewhere...)
http://aspe.hhs.gov/poverty/09poverty.shtml
A QUESTION OF INTELLIGENCE: If your wife knew she already deposited the correct amount of money - why did she feed more to the machine - rather than requesting (not demanding) assistance from a manager... Does your wife possess the intellectual capacity to handle money? Is the reason you chose to make a public complaint on this forum because you could remain anonymous as you would appear as a fool or a fraud...