Yeah, one of the items was third party, one was Newegg. But I agree - you can't outcompete Amazon by trying to be Amazon.
Sweetwater (who I mentioned upthread) are great because they do musical instruments (and related) and nothing else. Deep domain knowledge, rich and well organized catalog, community of music nerds, and (as far as I've noticed) no third party junk.
A Newegg could theoretically do the same for computers and peripherals. (Find me all motherboards compatible with i7 and ddr4, with usbc, blinkenlights and onboard wifi - much easier on Newegg than Amazon, but unfortunately it suffers from the aforementioned issues).