@Jamie I am having exactly the same issue and agree with your opinion, are you able to find a solution to that yet?

In Demo I noticed that when viewing the delivery order and from here printing the picking list the source of the product [A1232] iPad Mini is WH/Stock. If I then choose transfer, the correct and complete source location WH/Stock/Shelf 1 is shown in a popup. Going back to the delivery order by choosing cancel and then printing the picking list again, the complete source location is shown WH/Stock/Shelf 1. Weird, because I chose cancel so there was no status change. 

I would like the complete source location on the picking list without choosing transfer (and then cancel) first. The correct order in my opinion is:

1. choose Delivery Order
2. print Picking List (with complete source location)
3. pick products in stock
4. choose transfer in Delivery Order

You need to modify your Qweb report view for the stock.picking report.

1. Login to a user with Technical Features enabled.  Navigate to Settings / Reports / Reports.
2. Choose the Picking report.
3. Click Search associated QWeb views
4. Backup the report_picking view by duplicating it and naming report_picking_backup
5. Modify the XML table so that it shows you the information you are looking for.

Note: I did not dig into exactly which fields you will need to pull to output the Rack/Shelf/Bin as setup on your products.  For that, you should reference https://www.odoo.com/documentation/8.0/reference/qweb.html