This isn't a comment on the "realness" of the video but there's an edit at :30 when it's picking up the bag right?
I think, after watching it frame by frame, the bad is being quickly grabbed by the "hands" and over (what looks like, to my untrained eye) 2 frames the bag gets squashed a little.
i think the hand motion is hidden by the arm, the bag is being held in a slightly weird way which makes it change shape unexpectedly and the hand closes very fast (hard?) making the shape change quickly.
The throw just looks like the bag has all of the weight in the bottom.
I also note the "foot tapping". It's not just tapping though, it's kind of appearing and disappearing.
Certainly looks fishy to me.