I doubt they offer this as a free service. They probably checked the serial number to determine the age and since it was within the warranty period, they did not charge me. The written policy of no warranty transfers is probably to limit their potential liability, however depending on the situation will fix things without too much fuss.
When you see factory "refurbished" items for sale at various auction sites like Ubid.com it ususally comes with a lesser warranty (90 days instead of a couple years). Some of these items are new. They sell them on clearance / closeout as refurbished so they can increase their profits on the fire sale by shortening warranty period.