The elephant in the room is that Amazon keeps increasing their fees.

So if someone needs to adjust the price to accommodate Amazon fees, on Amazon, they're penalized.

Not to mention increasing ad costs, which at this point is another fee.

It's not for the benefit of the consumer, it's for the benefit of Amazon: Amazon wants people to buy on Amazon at the lowest cost for the consumer and at the highest margin for Amazon - they won't sacrifice their fees.