You said — “This statement puzzles me. What force would cause the tool bag to float away?”
No force... just “inertia” — a moving object keeps moving and a stationary object stays stationary (unless acted upon by a force).
Soooo..., unless you place it *precisely* still (it’s never “still”, but at least “still” in relation to your own movement) — it will keep on moving, ever-so-slowly — until it’s out of reach, by the next time you look at it.
ALSO, all you have to do is “bump” it (and not know you just did that) and, once again, it would “ever-so-slowly” float away, out of normal reach...
It’s really *so, so, so* easy for things to float away that the *real problem* is how to keep things *from floating away*....
There can be no "inertia" without force. The "bump", which is not mentioned in the article, was apparently the "force" I inquired about. Thank you.