Because people have been misinformed by the popular media. It is true that egg yolks are high in fat and cholesterol, but they are also high in nutrients. Here is an actual quote from the American Egg Board: "Eggs are a naturally nutrient-dense food, which means they have a high proportion of nutrients to calories. One large egg has only 75 calories and provides 13 essential nutrients in varying amounts. Eggs are an excellent source of choline and a good source of the highest quality protein and riboflavin. Many of the egg’s incredible nutrients are found in the egg yolk, including choline, folate, lutein, zeaxanthin and vitamin D. The yolk also includes healthy monosaturated and polyunsaturated fats and almost half of the high-quality protein found in eggs." In other words whole eggs are the perfect food source so you should eat the yolk and the white.
Your body makes cholesterol naturally and it is only in a small amount of people that the body gets too much cholesterol from food sources. Besides, the myth that cholesterol causes heart disease is beginning to gain momentum as it is well known that the culprit is not cholesterol levels so much as homocysteine. Too low of cholesterol will actually cause death. Do your own research and you will find this is true. Eat your eggs and be happy as they are so good for you!
And yes, I know, I am giving you info that is not part of the government's mantra or the mainstream media's hype, but I am giving you info that is well researched and documented.
In the 1980's there was a sensationalized campaign that vilified eggs as evil. I kept eating them. Then it was found later on that they were not evil, but good for you. Then there was the alar scare and many people stopped buying apples, but I bought them. Do your own research, don't listen to the "experts" who are always changing their mind about what is healthy and what is not, and make up your own mind based on good research.