Thales' claim that all things are full of gods, should not be read as a confirmation of the mythological idea that the supernatural gods control nature. Instead, we can read this claim as the natural consequence of the view that all things derive from water. Thales almost certainly identified water as something divine (all the Presocratics seemed to identify their physis with divinity), and so everything in the world, as derivatives of water, would have a divine element to them.
Though Thales believed that water is divine he did not believe that water had human motivations, wants, desires, or even any interest at all in human society. Water was probably just divine for him in the sense that it was the source of the universe and perhaps also in the sense that it was the guiding or controlling force in nature. additionall The claim that all things are full of gods might also be read as saying something slightly more substantive than that all things derive from divine water: it might be read as the claim that even inanimate objects are ensouled or alive in some sense, perhaps because of their connection to water. In what sense these things should be seen as alive, becomes clear in the final piece of evidence we have for Thales' thought.
The claim that the soul produces motion seems to be an attempt to equate being alive, or having soul, with motive power. Taken together with the previous statement, we might conjecture that the property of being motive (i.e. being alive) derives from having some share in divinity (a share which all objects might automatically posses simply because they derive from water). This would certainly complement theories of some later Presocratics, including the two other Milesian philosophers who do seem to explicitly hold that eternal motion is part and parcel of divinity.
Thales, apparently in connection with this statement, pointed as evidence to the case of magnets. Magnets are inanimate objects, and yet they have the power to move iron. If even magnets have motive force, he seems to be arguing, then all things probably have motive force, hence all things are ensouled.
It seems very likely, from the evidence of this example, that the two claims—(1) all things are full of gods, and (2) the soul produces motion—are connected. Why would Thales be concerned to prove that inanimate objects have motive force (i.e. are ensouled) if he did not want to prove that all objects are ensouled? And if he did want to prove that all objects are ensouled, it seems plausible that this is, at least in part, what he meant by the claim that all things are full of gods (especially since soul and motive power seem to be intimately connected to divinity in the systems put forward by other Presocratics).