Why is tofu brain sold only at breakfast time and not all day?

Because many people get up late in the morning and don't want to spend a lot of time cooking breakfast, they go out and buy some to eat at home, which saves time. Eating tofu brain has become a habit of many people for breakfast. Because there are more people who buy tofu brain in the morning, it is easy to make money in business, but few people buy it during the day and can't sell much in a day. Tofu brain has no motivation to make money, so many people don't always sell tofu brain during the day.