stupid seller

Looks like one seller sold out "to market" for over 200,000 shares, decimating the sp by 20% in the process (all trades were marked at exactly the same time, 13:21:14PM).

Why would anyone give up over $4000 of potential dividends and/or not wait for a higher sell price? I understand desperation, but this sucks (since it shows up as multiple transactions, when it is just the one sell transaction over a number of buyers).