I manufacture and sell to WalMart and know of the stipulations that they set.  They demand that slow selling products be returned for credit.  They threaten major chargeback for late deliveries or packing discrepancies, and so much more.  The owner of my company always says to me "bigger isn't always better"!

Surely GNC is a big-box store in the nutritional supplment industry.  They probably have similar stipulations that CEN couldn't meet or didn't agree with.

www.marsplastics.com

Keith