There are few things more American than hot dogs, and Americans eat an estimated 20 billion hot dogs each year. While most of these are purchased in-store, a good number get sold by street vendors and at sporting events. Given these statistics, hot dogs seem the perfect fast food option, but there’s one reason they’ve been left off the menu.

In the past, fast food restaurants have tried selling hot dogs, but the item rarely lasts long. McDonald’s McHotDogs were eventually pulled off the menu, while Burger King’s attempt was dubbed “limp” and “disgusting” by the New York Post. The issue is that these stores are set up for grilling burgers, and grilling is not a quick or easy method for cooking hot dogs.

According to professor Mike von Massow, “Grilling a hot dog is more difficult than grilling a burger,” because their shape makes them harder to evenly cook, but the alternatives — microwaving or roller-heating — don’t provide a mouth-watering experience. Plus, hot dogs differ drastically from city to city, making it difficult to cater to everyone’s tastes on a large scale.