There is no other reason provided for his desire to keep fire away from humanity; it is not out of a prudent and paternal fear of fire's destructive powers, nor because of something divine in the very essence of fire that is not to be sullied by human hands, but merely because it is part of the "stuff of life," and the gods do not feel like sharing. It is one more way in which Zeus can feel superior to man, and though this type of petty selfishness might not be very becoming to the king of gods in the Greek pantheon, maker of thunder and lover of swans, it is certainly appropriate for a villain.
So, too, is the ingenuity with which Zeus goes about punishing mankind for Prometheus' stolen gift. He does not simply strike all men dead, or create a terrible monster to roam the land eating livestock and trampling children. Instead, he has a woman created with immense beauty, skill as a weaver, and the "morals of a bitch" (line 76). This is Pandora, who was physically shaped out of the earth by Hephaistos, educated by Athene and Aphrodite, and given her moral fortitude (or lack thereof) by the changeable and flighty Hermes. With this pedigree, it is hardly surprising that the beautiful Pandora leaves her weaving at the earliest opportunity to open the box she was forbidden to even peek inside, thus releasing all kinds of evil an strife into the world. It is also unfortunately unsurprising that this is the method Zeus uses to punish mankind for all time.
By having Pandora be the cause of the release...
Though he had full knowledge of the box of evils and of Pandora's nature -- as she had been created at his express command and according to his explicit directions -- he can claim that he had nothing to do with releasing all of the turmoil and badness in the world by pointing the finger at Pandora. In this way, Zeus is able to abdicate all responsibility. After selfishly withholding fire from mankind and petulantly over-reacting when Prometheus managed to sneak it past him and bring t to the world anyway, Zeus is still able -- again through his ingenuity -- to avoid all direct responsibility for the issue. This is the third and final sign of his villainy, as it was with the Air Spirits and Mugulu -- not only did he behave in dastardly and villainous ways, but this villainy is in fact compounded by denial of his own responsibility in the matter.
Conclusion
The cultures that produced these myths in the Americas, Africa, and Europe were very different, just as the myths that they created show very different views of the world in some aspects. In other aspects, however, they are largely the same. Though villains and villainous behavior might be a strange area in which to find a common ground with other cultures, the similarities in the villains detailed above demonstrates how similar and common these things really are. It is not only in our good qualities but also in our bad that we humans are truly one people.
