I worked many moons ago as Distribution Manager for W M Lighting in Northampton. They were the suppliers of lighting to most of the large DIY, supermarkets and small independent electrical outlets. Returns were a major headache and for most outlets the policy was to destroy rather than go through the hassle of repackaging, storing goods until there was sufficient for a collection, returning, raising invoices, raising delivery notes, obtaining credit notes, safety testing, repackaging again etc.