Get a 2nd opinion...
I suppose that's all together possible - but I would
definitely get a second opinion before spending a dime! When I picked up my e46 it had 30k on it - I had the dealer change all 4 pads at about 35k (squeeking brakes, apparently them OEM pads were recalled on my particular build), every ounce of work was covered under warranty.
I can't imagine your rotors would be through after only 30k - they
should be able to machine/resurface them, the pads (though you should check to see if
yours can be replaced 'due to the recall' as well) you could probably replace. And though Akakubi is a good source for info (being an autoX guy), I just don't see a $750 service visit after only 30k!
**Alright, just called my dealer and referenced your scenerio; Tech stated that the rotors "typically" need replacement around 30k-45k miles. He stated for front pads & rotors you're looking at $490. He stated the rear pads & rotors probably do not require service this early (hence the price difference).
There's bound to be a way around some of the cost, though. If you're anything like me, you'll try to (at the very least) get the pads covered under warranty. Usually when you're spending a few hundred the dealer will work with you.