Refer a friend bonuses: do they actually pay or is it a scam

Every few weeks I see those refer a friend deals pop up - like, bring your buddy in and you both supposedly get some easy money or free bets. Seems simple but I never really trusted it, mostly cause the requirements are usually buried in fine print. Half the time, the buddy has to wager a crazy amount or stick around for way longer than they want just for me to get the bonus.

I've only tried it once and the payout took forever, even after we both did what was needed. Sometimes I wonder if it's really worth bugging my friends over, especially if the site is gonna make it a pain to claim. Anyone actually had a good experience with these? Or is it just another one of those promo hooks that sound a lot better than they pay out?