NON specific SPOILER warning - can't recall what book
Interesting scenario: "joe the black court vamp may feel something for humans he cared about in life but if hes hungry hes not going to be motivated by said feeling to not eat them, a bc vamp may be eating his/her own child and think ah i reconize this one, interesting. This should probably be upsetting me but it tastes so /good/."
I'll start with "of course YMMV", and say that I see more a continuum than an either/or. Vamps (to run with that example) are so driven by their hunger that "er... who was that?" is and can only easily be an afterthought. Human beings are driven as well by various things, only 1-relatively less forcefully and 2-they are really good at denial.
Isn't there a point in one of the books where a powerful goodie comments that while humans certainly do have the power of choice, they don't use it very much at all. So in my world monsters do have choice, perhaps less so than humans, but they have it, few of them use it.