There are three major factors that contribute to fast food’s popularity: inexpensive, easy, and reasonably appetizing.
1. Inexpensive
A major reason junk food is so popular is because you can get a large amount of food for very little money. Almost any fast food restaurant has a ‘dollar’ menu or something similar. You can get a full meal for merely a few dollars.
It’s same situation at the grocery store. Healthy foods, such as fresh produce, tend to be more expensive, while high-fat and high-sodium meals and snacks are much cheaper. A cup of instant ramen noodles costs less than 50 cents, while a fresh orange costs a dollar.
Although a lot of junk food is inexpensive financially, I think you could argue that these foods are more expensive in the long term because of the impact on health.
2. Convenience
This goes hand in hand with the low cost. Junk food is readily available in gas stations, corner stores, and vending machines. Remember those instant ramen noodle cups from the grocery store? They’re ready in minutes, and you can store them in your cabinet for a long time.
Unsurprisingly, fast foods are called fast for a reason. If you go to a fast food restaurant and order food, you can eat it a minute or two later. Or you can stay in your car and eat it as you drive away.
3. Sweet, fatty, and salty
Junk foods aren’t exactly known for their complicated flavors. They’re usually either sweet, fatty, salty, or all three. These simple tastes might be preferable to some people, like children who dislike the taste of vegetables.
But it’s not just about flavor. People are known to enjoy combinations of fat and sugar. Fat makes for smooth, creamy textures. Starchy salty foods like potato chips have a nice crunch. This isn’t to say that healthy foods don’t have good texture as well, but it may be more of an acquired taste.