The don't get a direct kickback, but there is an absolutely massive campaign to influence prescription decisions right out in the open:

https://www.bmj.com/content/385/bmj.q781

FTA:

> Some 57% of US doctors received more than $12bn in payments related to medical drugs or devices from manufacturers between 2013 and 2022, an analysis has found.1 “Despite evidence that financial conflicts of interest may influence physician prescribing and may damage patients’ trust in medical professionals, such payments remain pervasive,” says the letter in JAMA.