I thought "shilling" meant that a seller has someone they know bid on an item to get the price up. This book is a BIN. Not sure what you mean about them "shilling" ????
From Merriam-Webster:
Main Entry: 2shill Function: noun Etymology: perhaps short for shillaber, of unknown origin Date: circa 1916 1 a: one who acts as a decoy (as for a pitchman or gambler) b: one who makes a sales pitch or serves as a promoter