If you and your spouse are dressed almost identically, or if you are carrying your passport in a thing around your neck, or if you are wearing any form of footwear or pants that you clearly purchased specifically to wear on airplanes, or if you make it obvious (by repeatedly turning around and talking to passengers in seats not adjacent to yours) that you are travelling with a group, the charge is fifty dollars.
I would add that if your entire family is dressed alike, then it will be 50 dollars per infraction. :-)