It's equally common for indie authors to purchase reviews through paid review services. (edwardsbrothersmalloy.com)
Places like Kirkus and Midwest Book Review do offer paid review services, but these are handled by trained, professional reviewers who will objectively weigh the merits of your work. (millcitypress.net)
Ostensibly, this includes reviews from paid review services such as Kirkus, but also includes reviews from anyone to whom the author's book was gifted, as Amazon considers this a form of compensation. (indiesunlimited.com)