alt Hacker NewsThe title is as misleading as they could make it while being technically correct.
The study found that it offered different products to users depending on context inferred from their other data. If you have a history of buying expensive clothes and luxury items, you're going to be offered more expensive clothes and more luxurious items.
The chatbots were not showing different prices for the same products.
As you note, it's going to be based on what the LLM knows about the user, and as any good predictor knows, rich people like to buy expensive stuff.
Whether or not the article has examples, it would be surprising (an LLM prediction failure) if this expected behavior did not extend to different prices for different users, e.g. recommending the rich guy the Whole Foods bananas and the poor guy the Walmart bananas.