Is Amazon even supposed to be a reasonable place for small scale sellers to try to operate? The entire mechanism of credit cards and large scale markets is base

Is Amazon even supposed to be a reasonable place for small scale sellers to try to operate? The entire mechanism of credit cards and large scale markets is based on the idea that you reduce user friction in order to get more sales en aggregate. Can you imagine Best Buy caring "Visa let a fraudster keep the refrigerator they purchased from us and even refunded them $3000"? Something like that probably happens every week. If you care about every individual sale you need entirely different sales apparatus and pipeline than something like Amazon, for whom we have also heard stories recently here on HN of them shipping multiple items to someone and just telling the customer not to bother returning it as it will be more trouble for everyone than it is really worth it to them.