[metalliqaz]

Well, we can assume that they knew not to look directly at the Sun on a normal day, right? So there was perhaps already an understanding that caution was warranted.

But how do you know they didn't get eye damage? Seems reasonable to think that people did sustain damage to varying degrees. It still happens today... not even that rare, actually.

Also, assuming they weren't running for cover due to mistaking a total solar eclipse as a bad omen, they may have been interested in other things that prevented them from staring for extended periods. The 360 degree sunset, for example.