Your movies "immediately" get credited as being "back to the sender" when they are scanned in the store. Obviously, they are not shipping movies 24 hours a day. But they will be sent out as soon as the next shipment would ordinarily get done. For example, if you bring your dvd back to the...
And now the stores have laptops with internet access so you can change your que right in the store. And have you ever had a netflix dvd that was damaged? You have to wait days to get a replacement. With being able to swap a damaged dvd for a good one (for free)at a brick and mortor Blockbuster...