Originally Posted by PatNY
Not only are you dismissing cost and size as reasons to not add in SD cards, but the lost revenue if people use fewer cloud-based resources from Apple. So at least 3 reasons exist for Apple to leave out SD cards in mobile devices that don't exist for the widgets.
This. There is a huge margin on the extra capacity, what costs the consumer $100 costs apple only a tiny fraction of that. Offering an SD card would mean more people would gravitate towards lower capacities, knowing they can always use an SD card if needed, hurting the bottom line.