Yup. I tried selling on Amazon and ended up back on ebay because perfectly working stuff was being returned and I had to eat the cost of shipping both ways.
There are some others, bhphoto being a good one, but many of the online retailers do not have free shipping and many also have return fees. That’s where Amazon saw a way to steal customers away.
Most people want the question free returns, that’s really the thing keeping amazon afloat compared to say eBay or aliexpress. Sure you can get the stuff directly from China in most cases, but you have to wait for a month for it to arrive and hope you don’t need to return it.
As for local stores, they always cost more because of the cost of doing business, which is why Amazon is cheaper and faster to deliver.
All that said, as long as you can wait a few days, there is no need to pay for Prime, you can still get all the stuff shipped for free if you just wait until you have 45 bucks of stuff to buy.