Actually, I don't take vendor into consideration either, except just for an example's sake.
As I say in the articles, I just post Newegg prices and links because their site is (in my mind) by far the easiest to navigate and they have pretty much the best selection anywhere.
I would always encourage everyone to look around for solid vendors that might provide a better deal, although I generally think getting everything from a single vendor (if possible) is a good idea.
Things can get really crazy if you are trying to get parts from three different companies and trying to RMA to a fourth. It's nice to deal with one...especially one that has a good reputation for customer service.
I know Newegg isn't always the cheapest (in fact they probably never are), but I trust them because I've used them more times than I can count, and my experiences have always been good. Where other people buy components from is entirely up to them.