Personalised ads favour aggressive vendors offering less quality and higher prices:

“Ads shown were pitching more expensive products from lower-quality vendors than identical products that showed up in a simple web search [and] were 10% more expensive“

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4398428

🐦🔗: https://n.respublicae.eu/paultang/status/1646053452617863168