... And eBay/Paypal won their era's fight because they offered the better experience compared to the others, they were considered the safe and reliable one.
Early web shopping really was wild. And not the good kind.
And then came Amazon an roller-steam them all. And in my opinion it's because of their super buyer-friendly, stress free experience.
Every time you would buy a book from them, and you were happy that they gave you the best possible price, they didn't give you hard time when the book was lost in the mail or you wanted to return it because the sent you the wrong book, or whatever, your trust in them would increase.
Once you consumers trust you with buying A, selling them B, is just a matter of making it available through your store.
I see a lot of online stores, operating the old way; with hidden discounts, dedicated seller-teams trying to sell stuff to you, pushing back when you want to return an item, etc. and can't help thinking how they are ever alive.
Early web shopping really was wild. And not the good kind.