Good question, however, the point is human can destroy a planet. Demons on other hand are limited. We humans are much higher in rank. Why devalue yourself?
True at least for the demons described in documents related to the bible and in the bible itself. Powerful humans actually enslaved demons to help construct the temple of solomon. Here is a bit of a (extra biblical) document describing an exchange between demons and the King. ;
42. So I Solomon, having heard and wondered, sealed them with my ring; and since they were so considerable, I bade them dig the foundations of the Temple of God. For the length of it was 250 cubits. And I bade them be industrious, and with one murmur of joint protest they began to perform the tasks enjoined.
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43. But I Solomon glorified the Lord, and bade another demon come before me. And there was brought to me a demon having all the limbs of a man, but without a head. And I, seeing him, said to him: "Tell me, who art thou?'' And he answered: "I am a demon." So I said to him: "Which?" And he answered me: "I am called Envy. For I delight to devour heads, being desirous to secure for myself a head; but I do not eat enough, but am anxious to have such a head as thou hast."
The Testament of Solomon
Demons are tricky and not to be trusted!
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