Man, that's a good price! Buy them out!
I found some at Home Depot once, and it was in ~10# boxes on clearance for real cheap. I bought them out, but it was only 300-400#.
Pelleted gypsum is identical to regular gypsum. It contains minute amounts of some type of gel to make the pellets hold together. Believe me, they will not sell anything that's harmful to people, pets, or wildlife without conspicuous labeling. Wal-Mart won't even sell fertilizer with phosphorous any more!
