Do I really need routine dealer service?

DrEvil

I've looked over the service schedule in my owners manual and other than an oil change, what is really done at an official "Dealer service"?
I get my oil changed at the Mobil One quick change place with full synthtic oil and high perf oil filter @ 5k miles.(they fill the washer fluid clean the windows and vac the car at the same time)The manual states that the car is reset to factory standards, whatever that means to those who have done some modding or alot.
Am I missing something here? Been working on cars since I was 14 years old(I'm 54 now) so I know my way arround the car.
I was just so turned off by the dealer when the finance guy tried to push the extended warrenty on me " ... why the oil change cost $95.00. With the warrenty it's free..."
I just don't know if I need to go back.
Any input?