My question here is this.. Why do I need to pay big bucks for this service? Can I skip this at this moment?

I have a 01 clk 430
In the past 5k miles I replaced the following:

Front disk pads and rotors
coolant
brake fluid
fuel filter
air filters
cabin air filter
Oil
oil filter

what else should I do? it has 50,500 miles

 

oh yeah i forgot to say that B service says I need it in 8400 miles.. I am planning on just doing the oil change and air filters (engine) is that wise? and if the rear break sensors warningpop up I will replace them too..