yup, my dealer also wanted in the neighborhood of 175 for the flaps.(installed) added to the price of the Hummer!
She was hell bent on gettin me to get them and said i'd be back in a day wanting to add them. I told her i got some(better ones)off ebay for 50bucks (i really did) and she looked like someone ran over her puppy. I think the sales people have a lot riding on their customers purchasing the extras.