Lots of guys have a job & are very busy, & don't have time to cruise the net, to find the best price for stuff they want.
I'm retired & have time to look for the best prices. So, I like to post my findings on a few Pontiac sites, in order to help fellow Pontiac guys find stuff they want, & save a few bucks in the process. Some guys have plenty of money to spend & don't care what parts cost.
BUT, I've always been a low budget Pontiac guy. So, I, and other low budget guys might appreciate links to the best price, even if it happens to be on Ebay. The fact is, as a general rule, I've found the best prices to usually be on either Amazon, Ebay, or Summit. Not ALWAYS, but most of the time.
I suppose this may be just another of those topics about which opinions differ.