Buying from an alternative ecommerce site usually sucks: you have to register for every website, enter your address, payment information and other information, they may leak data or store it improperly, you may not know the reputation of the website or business, you can't easily compare products with other vendors and more. Amazon and ebay offer a centralized good experience and you know you can trust them with your purchase. They benefit the consumer by aggregating many businesses so it fosters competition lowering prices but they have so much power and they have done some anti consumer moves. Their fees could also be a problem.
The same way mastodon offers a viable alternative to the deadbird platform and slice power to small instances while getting a better user experience. (And lemmy to Reddit.) A fediverse version of ecommerce could perhaps be viable: federated ecommerce that aggregates small business shops, handle the user details and let the business access it when you hit buy. Activity pub to communicate the listings and purchase orders. I am not a programmer and don't know the technical implementations of it. So what do you think?
I hate the marketplace thing, and the harder it became to filter out third parties the more I ordered outside of amazon.
I came to amazon back then because it was one seller offering most I cared about, and a single contact for everything. More and more stuff is now only available via 3rd parties - and with that I can just order stuff bypassing amazon.
Not to mention the ridiculous markup on everything. The last few times I've looked on there the prices for generic chinese garbage was higher than name brand stuff directly from the manufacturers website. These days I'll stop literally anywhere besides amazon.
That has happened to me. Amazon on itself was reliable and good, all the issues I had were marketplace related but so bad I look for alternatives for every purchase now.