Someone who owns a Tesla and likes the experience , will most likely recommend it and can point point them to Tesla referral program (not sure if they still have it) - they will earn more than most of Amazon Referral fees, and it's most likely and honest recommendation. Though definitely biased.
Your only protection is to be aware of bias and do your own research if you are inclined to buy something recommended.
Or not, because that's why we turn to experts/influencers (no matter if it's a friend/family member/blogger/vlogger) in some matters you're not comfortable with or you don't care enough/don't want to put the time to research.
So yeah, I wish I had a fee for every sales made from friends/family/internet strangers that asked for my recommendation.