Interestingly (to me), we checked Home Depot, Lowes and Costco and the best deal was found on LG's website itself. In LG's case, delivery of the new units and haul away of the old units is included in the price. The other three charge you $50 each ($100 total) to haul away the old washer and dryer.
My wife does the same thing for our vacations. She will go to the website of the resort we plan on staying and join their "preferred member" program and then book it through the hotel. Turns out to be more economical and a better deal than using an agency like Expedia.com, Cheap Carribean Vacations.com, etc.