When there had been sucessive famines and long time famine in a country, the people that time in order to get sruvive themselves they tried to eat everything they got in hands - roots, grasses, insects on land and in sea, birds, dogs etc. Having eaten thoses things for years and years succesive years of famine for long famine, it has become a habit of people of that country to eat all kinds of insects, birds and dogs even after there is no famine. For good example see the Chinese people in China and African people in Africa.
Habits die hard is the saying. Whatever bee he circumstances, once taste developed on eatables is difficult to discontinue. Knowingly fast food is the worst for health, people crave for that. Because fat is the sixth taste and many insects including white ants are rich in them.