Concession stands in America and Japan

I helped a small concession stand at a public sport field in West Seattle during marching bands’ performance. This concession stand was for a fund raising event for Seattle All City Band. I doubted to make much money by selling food.
The menu was very simple. Menu included 3 types of Pizza, hot dogs, chili dogs, and popcorn. Chips and candies were also sold. Vitamin drinks, pops and water was the choice of drink. The Pizza was picked up from takeout place near by and kept warm in the clear show case. Hot dog was steaming in the warmer. Large canned Chili was emptied to be warmed up in the large pot. Popcorn making machine was popping corn kernels. Drinks were cooled in the large buckets full of ice. I stationed at the hot dog area. Pizza was sold more than hot dogs or chili dogs. The most popular item was popcorn. Because of the price, customers bought a large bag of popcorn for 1 dollar while chili dog cost 4 dollars. I was surprised to see many items and drinks were sold.
Here I thought about Japanese concession stand at the baseball stadium in Japan. I found website of Nagoya Dome where residents of Nagoya often to go to see Japanese baseball games. The link shows the photos of the concession stands and food sold.
The stands at Nagoya Dome sells, Tama Ben or Ball box lunch, snacks, pudding(Dragon and koala bear together named Doara Purin) , and shaved ice called gut’s ice. It seems that hot dogs and pizza are not there. Most Tama-ben contains cooked rice according to Japanese description. The names of the Bento box are very interesting. Strike Bento, Full base Home run Bento, Sports Bento are the examples.
How about American ones? I found a blog “Where to find the best baseball stadium food” (http://blog.ratestogo.com/baseball-stadium-food/) The baseball stadium food seems to be Hot dogs, fries, Sandwiches, Cotton candies, and other American’s favorite meals .
If you have an opportunity to go to Japan, it may be interesting to go see a baseball game and check out the concession stand there.