This is why I DIY my oil changes, both the cost and time factor. Grabbing the supplies while I am at the store anyway means the time I would spend driving to/from the dealer is used to do the work and the time waiting at the dealer is time saved, so overall less time involved too.
That said, not everyone is capable or interested in DIY. As already stated, there are usually coupons or 3rd party less expensive alternates, but just walking into any dealer and handing over the keys without inquiring on pricing is the best way to pay the most. Calling ahead and asking about any specials will usually flush out any coupons as will asking if they will match a competitor price or coupon. Most times any discussion after the work is done and the bill is in hand is wasted breath, and that's not just true of repair shops.
2007 MDX Tech Billet Silver
2007 Honda Odyssey EX-L Nav/Res
30+ Years Automotive & Related Industry Experience