I don't think they're blind, they're just not particularly agile, so they bump into stuff alot. Unlike most flying insects, they only fly for a few weeks every 17 years, and they do so in such numbers that predators don't make a dent. So agility wasn't a particularly important survival trait.
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|...............| We live in the nick of times.
| Len 17, Wid 3 |
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