Brand. Brand is the key differentiating factor when it comes to influencing purchase decisions in a mature market. And Amazon's marketplace is a race to the bottom cesspool that's antithetical to customer loyalty.
Consider this search for "tablet arm":

Which of these should I choose?
- Three of the four have relatively similar ratings.
- All of them are within the same price point.
- None of them are from a name brand I know I can trust.
Such indecision! I could spend 20 minutes scouring through the reviews, but who knows which are real and which are fake these days. Or, I could buy them all and return the ones I don't want. But packaging stuff back up and taking to UPS is a hassle.
For exactly this reason, I went to Best Buy yesterday (for the first time in decades), looked at video cameras, and bought a nice Canon for a cheaper price than it was listed on Amazon.
I like brands. Brands mean I can form trusting, long-term customer relationships with companies. The Amazon marketplace is overrun with knock-off products from generic drop shippers — bad and getting worse.