I understand your approach. There are times I do the same, do my research, know what I want, go to shop, pay and byebye. However, now I am paying for a product +/- $1k, so I would prefer to 'discuss' or 'talk abit' rather than "pay and go".
Maybe it is also because I view service to be quite important.
Or maybe I just need some assurance on my choice of purchase. :S no one will be able to discuss with me or accompany me when I make my purchase, and I am a super newbie, so I thought that maybe the salesman will be able to make certain recommendations or give some opinions. Of course like mentioned, they will probably just push the product with the highest profit margin.