I've done bags before.  They work. Very little spoilage as long as the corn is cool/dryish. Definitely move before it gets warm outside if there's any amount of moisture to the corn.  I did mess up a bit and put them on a flatter area next to our bin site.  They did act like a "dam" and one bag was holding water up during spring snow melt.  Had about 10" water pushing up next to the bag.  Not a fun time.  Run the bag in the direction of natural water flow.  Or just move them before the snow melts!

Deer here love to walk on top of them like goats for some reason and poke holes with their hooves.  Gorilla tape is your friend.  Lead is your friend.

I don't remember the cost at the time but I believe it was around $.15/bu with the machine rental and bag.  This was about 10 years ago though :)  I think bags are around .07 ish now?

Anyways, no reason one couldn't pile it in a machine shed floor if the floor is thick enough and/or pile it outside under a tarp if it's dry enough.  The elevator here makes PILES.  Why can't you with the same provisions?  Screw aeration wouldn't be dumb.  2009 was a wet year here and a ton of corn was piled around 25%.  A ton of those piles started on fire as well.  A little common sense goes a long way to grain storage.  Keep it dry, cool and out of the elements as much as possible.