Those DINO bags or Totes or whatever they're called are an interesting idea. Those ones look like a manageable size.
The ones I've seen at my friends' farm are approximately 4' square by about 5' or so tall. They get distillers grain in them.
Come to think of it, I've seen some smaller ones along the road when the hydro crews are replacing hydro poles filled with aggregate.
Might just have to stop and ask about them next time I see a crew out replacing poles.