IIRC it was a few years back but the brand they sell - Arctic Mice? - had some distribution issues where the stock wouldn't be shipped in a refrigerated truck and so the rodents would thaw during shipping, then get re-frozen at the store. This could allow bacteria to build up on the outside of the feeder. When I had two snakes I fed them (this was before I knew about online suppliers) and on several occasions the feeders definitely smelled "off".
From a price and quality standpoint you'll do better ordering from a reputable online vendor.