Why did Giants eat people?

In The Book of Numbers, when the twelve spies returned to tell Moses and the others what they saw in the land, they made mention of how they saw giants living in Canaan,

And there we saw the giants, the sons of Anak, which come of the giants: and we were in our own sight as grasshoppers, and so we were in their sight. Numbers 13:33

But they also mentioned something else,

The land, through which we have gone to search it, is a land that eateth up the inhabitants thereof, and all the people that we saw in it are men of a great stature.

This is basically implying that there were man-eating giants in the land of Canaan, which is exactly why the people of Israel were so terrified to enter the promised land. (On an unrelated note, many people will say that these weren't literal giants but really tall people. And I say, "Why would 600,000 people be scared of a tall person?" These individuals had to have been enormous in size and have fearsome reputations for making almost a million people so scared that they'd rather go back into slavery.)

And you know what? Every other single account of giants on Earth describes them as vicious, man-eating monsters, especially Jack and the Beanstalk, and that got me wondering, could there be an explanation for why giants enjoyed eating humans? Does anyone have an idea as to what made giants so hungry for human flesh.