It's a little too late to ask the question if you have already bought the warranty. Extended warranties are an additional profit center for the dealer, and also for the manufacturer. (If a dealer tries to sell you something, it is not because he likes you.) The manufacturer knows to the nickel how much the maintenance cost of a vehicle should be, and it prices the warranty accordingly. The manufacturer's estimated cost of the standard warranty is built into the price of the car.
If you are the kind of driver who abuses a car, then maybe an extended warranty makes sense. If you watch your fluid levels, do not race, and do not go off road, it is a waste of money.