> I’m not sure why Amazon didn’t just block non-verified-purchaser reviews, increasing spammer costs significantly. I don't think it'd do much good. There are

> I’m not sure why Amazon didn’t just block non-verified-purchaser reviews, increasing spammer costs significantly. I don't think it'd do much good. There are already large groups that subsidize verified purchases to get 5 star reviews. I read an article about it, confirmed some investigation on Facebook of on my own. Basically someone runs a Facebook group where sellers advertise free product, promising Paypal reimbursement of the purchase price in exchange for reviews. There are at least (or were, I haven't checked recently) hundreds of Facebook groups across many languages with thousands of members each doing these activities. The reviewers are randos who like free stuff, and I don't think anyone could detect them if they only casually participate in the review scams.