Why is African Safari trips so expensive?

safari travel
Restingfighter asked:

I understand that seeing exotic animals and nature to its fullest is a great thing and not anything like your local zoo, but it is a billion dollar industry in Africa, where does all that money go?

My dad and I traveled to Tanzania and spent $ 3,000 for only a week to see animals in Sarenghetti and lived by camp hotel. It was all worthy it.