mobster75:Actually my local shop offers free air (not nitrox) period. I'm pretty sure its regardless of whether or not you buy the tanks from them. But it got me wondering how common that is out there and what the going rate for an AL80 fill would be...
Your shop is clearly trying to bring in business by offering something that costs them money free. It's a great idea and might be a good loss leader to get people in the door, but its also extremely rare. Don't expect to find this just about anywhere, unless you are buying some expensive gear or servicing. Air fill prices tend to range from $4 up to $10 or more, although they are generally in the $4-$6 range.