Visual stock management and organization sounds like a powerful approach. I haven't seen much of it first-hand in any global health setting so far. Kenya seems to be using boxes to organize its vaccines, but not sure where the diluents go.
Beyond avoiding deadly confusion as Rudi suggests, it can be a powerful inventory management tool especially at health facilities. Ideally all the product of a kind are in a box so risk of loss and misplacement is reduced, time to find product and identify stock out is also reduced. Additionally, it is possible to use 2-compartment bin with a sort of visual safety stock to encourage replenishment to happen before the products runs out completely. Btw, such practice is very common and considered best practice in developed world retailers and pharmacies.
These are many advantages that definitely would make usage of bins to organize stock in bins in the fridge an intervention to try. Additional visuals, color coding, etc are all powerful cues for better management as well.
The main challenge from using bins in a fridge is the possibly poor usage of limited storage space. This can be limited if the bins are small enough such that you can remove some the empty ones from the fridge. Probably one wants a written sign on them or some color stickers. Some grouping of products in a same bins could be considered as well to make packing more efficient; for example to put diluents together separately from all dangerous substance.
Expanding the thread a little, I'd be curious of examples of settings where bin systems have been used at health facility level to learn from this experience.
Yann