Referral links equate to income for many bloggers who are into affiliate marketing. I'm okay with that since I'm rather used to it and I actively put affiliate/referral links.
The only thing is i hate people who promote their links just to make a sale, and not to help others first, but they claim that they just wanna help. It's obvious when they're doing that. Also, a disclosure of referral links is required by law in some countries (especially USA). Crap i forgot to put a disclosure for my links in Steemit.