same game parlay boost bad?

so i keep seeing these same game parlay boosts but every time i run the math the ev looks pretty rough, like you’re just stacking more juice for a little extra “bonus.” maybe i’m too used to squeezing the promos from blackjack tables where you can at least count on the expected value being more clear. feels like the boost is just a marketing thing and variance eats up your winnings unless you hit some miracle. am i missing a trick here or is it really just for the adrenaline chasers? anyone actually profit long term off these or just for fun only?