I think the 'passive player' is just a playstyle, there's nothing wrong with it, though it's not my choice. Both as GM and as a player, I prefer the players to have more of a say in the game's direction.
Players in an adventure path or more railroaded type of game should, imo, have a stronger expectation that the GM will entertain than players in other styles of games. The path/railroad GM should be using the biggest, most explosive set pieces he has, his most colourful NPCs, his most dramatic plot twists, and so forth, secure in the knowledge that the players won't avoid them.