Sure they mask human scent, taste like food to the fish, some even disperse bubbles or sparkly scale looking particles into the water but the fact that makes me a beleiver is their ability to lubricate a bait (especially soft plastics) which allow it to come through the thick stuff better without sticking to grass, wood, (all that underwater stuff), improve your hookup ratio, increase fishing time by not having to constantly be removing debris and repositioning worms on your hook before casting again. That makes at least a 3 fold advantage over non-scented baits