None, because people who glow in the dark don't need light bulbs.
Note: Topical to the Chernobyl Reactor disaster of 1984.
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Because he has such yuuuuge fans!
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If one side has one, the other side has to get one. Once launched, they cannot be recalled. When they land, they screw up everything forever.
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One; she designs the bulb to crawl up the wall, unscrew the old one, and screw itself in.
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At the Whale-weigh station.
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