> I don't see how this is a relevant factor. If you're a karen at a restaurant who constantly sends your food back for the tiniest of issues, how is that any different than if the interaction happened online, such as if amazon gave you a bad customer credit score for your excessive returns?

The difference is that the restaurant has a human evaluate if your complaints are valid while Amazon only sees statistics and doesn't care why you might have a high number of returns. The restaurant can also only realistically ban a few worst offenders before that becomes unmanageable for them while Amazon has no such cost associated why banning you. Then there is also the scope of the impact. You likely have many more alternative restaurants you can go to but no one really competes with Amazon as a whole.

> Word travels around, does it not?

Only in extreme cases. You won't be banned from all Restaurants in town just because Bob got offended. With a centralized credit score once you get flagged then those checking it will usually not even talk to you.