There is perhaps a fine line between being surprised by an unexpected revelation and being tricked. This game falls more on the side of tricking and railroading the player into playing the role of a despicable character. Why would anyone choose to play that role otherwise?
Also, stories that take place in metaphorical/allegorical settings rub me the wrong way. They generally are trying to preach to you, package some complex piece of life into a conveniently simple fantasy, or make interesting what would otherwise be obvious and banal.