Pieces from this large set surface rarely. I surmise that the set wasn't produced for more than perhaps 2-3 seasons, possibly because it didn't sell well. In my many years of collecting I have only seen ~6 differently shaped candy containers, with this listing being the first time I've seen this particular design. Given just how rare these pieces are, the ending price seems low to me.
Mark B. Ledenbach's vintage Halloween collectibles blog.