I would imagine they want to be able to ship the most product without taking up space and weight, so plastic bags are ultimately the way to go. Pallets with bags stacked on bags.
Most average growers don't go through as much of it as commercial ones do. I don't really think they would want the added bulkiness and cost of getting a nice container with every 25lb purchase. They just wanna tear it open and use it up quick. The waste would add up quick with all the plastic containers adding up.
FFS.. They could at least make a 25 lb zip lock bag like the 1kg bags they sell. It does look like a zip lock in there.
I keep mine stashed in square 5 gallon buckets, so I can pack it away tight in a small room. Round buckets waste space by design but work..