It's a pretty tough read if you don't have a strong stomach. However, as it has been pointed out, cultures vary. Many of these things, as noted, were meant to be medicinal or aphrodisiacs. Some of the others, also as noted became popular because it was all they had to eat. It's less culturally taboo to eat insects or fermented sharks than it is to eat each other.
Hunger is a great motivator. To paraphrase Andrew Zimmern, " If it's there, eat it".