No LOL, I have never and will never pay over sticker.
In my area there are a number of dealers, one of which, has a horrible reputation for gouging and charging extreme ADM. As an example, they want $20,000 over for a lightning order. The dealer 18 miles away is giving it to me for sticker. How does the gouging dealer stay in business? All I can figure is that it is a factor of people not doing just a little bit of leg work. If they did, these gouging dealers would just cease to exist; or come in line with normal pricing to stay in business.
I'm not laying judgment on your situation, just commenting on my own. If you were caught unable to get a reservation, and/or needed the vehicle sooner, then that starts painting a different picture and you have to deal with it the best way you can. As an aside, I am always glad when a poor demo vehicle gets a good loving home, and really, one benefit is that all the Gremlins should have been beat out of it.