Problem is that return policy for Amazon is excellent, but completely nonexistent or cumbersome with other suppliers. That in itself is pretty much a deal breaker for competitors.
I recently ordered a $100 drawer shelf for a 12U rolling AV cart. The shelf was deeper than described so it jutted past the back of the rack. I sought a return. For which NewEgg charged $70 in return freight and a $15 restocking fee. Meaning I lost $85 and a few hours of time because NewEgg wouldn’t stand by the specs on their site.
To add insult to injury, the first step of their return policy is a YouTube video. As if part returns are so complicated. Amazon blows. But not like this.
I’m just one data point. Maybe an exception. I will never do business with NE again (but I still love how they fight patent trolls)
