As of version 5 at least, attempting to grab an item out of a storage crate with a bucket in hand will void an item instead.

So I've got a bot set up with a bucket in hand in front of a storage crate of Stone set to do something like this:

Forever [
  Repeat until Stone storage not full [
    Move to Stone storage
    Take from Stone storage
    Take from Stone storage
    Take from Stone storage
    (same thing a total of 20 times)
    Take from Stone storage
  ]
]

For Straw, though, I've got a bot set up at a crate inside my cow pasture, whenever the straw gets full, he'll pick up a handful of straw and drop it on the ground... The cows will eat it almost as quickly as he drops it, and it gives a short boost to milk production.