What's all the "have to have" talk about food grade buckets and really about buckets at all?

If a person stores bulk in mylar w/absorbers and it's sealed, does it really matter what the mylar is inside of? the mylar protects the food, the "bucket/box/whatthehellever" protects the mylar from puncture etc correct?

so, wouldn't it be just as easy/safe to store sealed mylar in plastic bins that fit under the bed etc?

buckets are mainly, as you point out to protect the sealed mylar.  so no bucket required,  they're just convenient, easy to stack and move.  we have some sealed 1 gallon mylar bags full of oats sitting on the shelf in our medium term food storage.  

Your correct. The mylar IS the protective barrier. Technically you "could" use very clean gypsum buckets if you really wanted to. I've passed up literally thousands of them over the years.

Try to stick with containers that actually have held FOOD if your using used containers. I've used pickle buckets (even the evil cancer causing "green" ones... OMG I'm dying now LOL), donut icing and cake filling buckets, new buckets purchased from Ropak and 60 gallon pickle barrels.

What you want to AVOID is any container that held cleaners, chemicals, etc.