The notion that "Amazon has EVERYTHING" only works if you can actually count on the purchase to work. Once it becomes apparent that third-party sellers are crap and those items don't count, you're back to "Amazon has certain things."
And I'm not merely careful to filter stuff. Amazon is no longer my go-to in general. I do buy stuff from them sometimes, but they're not the first place I check for most things.
A less savvy buyer probably won't even do that. If they get burned too badly on an Amazon purchase, they'll just abandon Amazon, not learn which checkboxes mean "hide the scams."
This is my experience too. Since I can't trust Amazon entirely, I don't start there anymore.
If I have to do careful homework on the seller for any Amazon purchase anyway, it's just as easy to find a more niche e-commerce site, or use a dedicated marketplace like eBay or Craigslist.
I still use Amazon's dedicated product sites like Zappos or Diapers.com. I feel much confident I'm going to get what I ordered there than on Amazon.com.
Frankly, I don't think you're in the majority. Personally, I buy from third-party sellers a lot because I get two-day shipping free and it's easy to shop on Amazon. If I got badly burned I might change my behavior but so far I haven't. I wonder how many even notice the difference.
I just don't see how Amazon isn't the go to. Anything handled directly by Amazon generally has the most competitive pricing, near guarantee of two day delivery or faster, and far larger selection than any other individual store. I cannot think of any general purpose store off the top of my head I would prioritize over Amazon.
To be clear, there are some specific purchases I would not make over Amazon. Amazon's clothing section is a complete joke, for example. I also like B&H, and use them when buying high end equipment.
Amazon frequently has prices much higher than other places. It depends on the product, of course, but it's definitely not a situation where I can just buy from Amazon and be confident I got a good deal.
There isn't any general-purpose store I prioritize over Amazon, but usually I know which stores sell the things I want. For example, Home Depot often has better deals with less search hassle than Amazon for hardware stuff.
Personally I've been using Walmart for consumables (paper products, cat food & litter). Still use amazon for books (the dead tree variety) and the occasional electronic item. Delivery time is comparable, and the free shipping threshold is $50 IIRC, regardless of what you're shipping (e.g. 100lbs of cat litter).
Amazon doesn't have close to competitive pricing, even before you factor in cost of Prime and/or slow shipping times from random 3rd party vendors and/or free shipping minimums.
My go-to is now froogle.com (Google's product advert index). It used to be Amazon, but they have way too many issues now.
I started doing comparative shopping via the local trovaprezzi.it since amazon collapsed third party seller inventories by sku and seldom buy from amazon today unless is from amazon itself (not even warehouse) and still I return a third of purchases
Shame because I previously bought dozens of books completely hassle-free
And I'm not merely careful to filter stuff. Amazon is no longer my go-to in general. I do buy stuff from them sometimes, but they're not the first place I check for most things.
A less savvy buyer probably won't even do that. If they get burned too badly on an Amazon purchase, they'll just abandon Amazon, not learn which checkboxes mean "hide the scams."