You can definitely do better but I can understand why some people may skip it. I could have done the affiliate program but I ended up going to a volume dealer. The difference in price is about $3500. I can grab a one way flight for $250-$450 and even with break in, I should be able to make it home on a tank of gas and in about 9-10 hours, but lets call it $150 in gas. For me, it was worth it. I can see how for others, especially those paying for freight, it just might not be worth their time. I'm a cash buyer and the bottom line is important to me. I didn't get to be a cash buyer by not pinching every penny possible.
Generally speaking, invoice is the absolute highest you should pay for any vehicle, ever. In this market, dealerships are whining over lost markup because of affiliate pricing.