I could have sworn I heard something once about how fast food chains put addictive chemicals in their food. For me, I don't have an addictive personality. There's nothing in my life I feel addicted to other than fast food. It's weird. I know the food is dogshit and I can make tastier stuff at home. But I also think about getting fast food all the time and have to stop myself from ordering it a lot. It does kind feel like a dopamine hit when I open up a bag of fast food and start digging in.
Most of the fast food places near me also clearly have fans pushing the smell of the food out their window, you can smell it from 20+ feet away. If you've had a long day, you're tired and hungry and suddenly you smell something super tasty and there's a nice, pleasant looking fast food restaurant that can satisfy that itch in a matter of minutes, it's not hard to see how that can be super tempting to a lot of people.