abuse and the hunt

here is something i just can't begin to comprehend...
it's called - animal cruelty... and it happens all of the time. and it's been particularly of interest lately given the vick case - michael vick fighting ring. but here is a headline from today:

3 dogs found skinned and mutilated

i can't begin to comprehend how people can torture animals. i can't begin to comprehend how anyone can feel good about taking the life of another creature - ever - in any circumstances short of being stuck on a deserted island with no other source of food... when it is completely unnecessary. it just makes my heart sink every time i read such a story.

what kind of sick, twisted people do these things?