Because of Mr. Laramie's blatant refusal to my request earler, I decided to undertake some research of my own. What I found seemed largely underwhelming.
Through word of mouth, rumour had proposed that in the 1970's and 80's there were experiments carried out in the fields outside of Brightmount. These were tests to conduct lightning for purposes of demonstrating the capabilities of different designs of lightning rods. One particular type, what they referred to as the dissapator, was meant to scatter lightning rather than absorb and ground it. The result was an event that caused the facility to burn to the ground. The people I spoke to seemed largely convinced that this happened, and even said that the records of the experiments can be found in the public access of the town archive in the library.
Initially, I was unsure as to what relation this had to the Seed Eater, until someone pointed out to me that, "the kids are taken after the lightning strikes. Always." This made me reconsider much of what I knew about the Seed Eater. I believe that we've finally detected a pattern. The lightning is a harbinger of sorts. It doesn't happen every thunderstorm, but when it does happen, it comes after the lightning.
Also, we must consider the "black cloud" described. It is my belief that it disguises itself in the storm - using it as a type of camouflage. The Seed Eater appears during or after a storm, maybe hoping that it goes unnoticed, and it quietly takes someone.
Maybe I'm just jumping to conclusions...