OK, my reply to this question is behind a spoiler. Read it last, because I think it will offend an Alpha.
Um, yes, I'd say that LIEs and LSEs and SLEs and some LSIs and almost no ILEs are carnivores who can sometimes take unfair advantage of others. Not that they all do, but I think they all can. Other types seem to either play very fair or mind their own business.
Personally, I try to protect the weak. I think I got this from growing up with an abusive mother and two younger sisters, but whatever. I have this basic urge to leave people better off than when I found them, and to step into trouble to correct it (my tritype is 368, the "Justice Fighter"*) when I see something that is not right.
Now, having said that, I'm not an angel and I'm sure that most of my actions have long-term detrimental consequences, but I'm only worse than others in this respect because I do more stuff. And all actions have some detrimental consequences.
Yes, I work with a female SEI-Fe and she's an absolutely terrific, super-high quality person, and now that you mention it, she acts like she's on the verge of being taken advantage of. Like she's cautious about every single thing. We get along fine, and she's nice to me (and vice-versa), but now that you point it out, she sometimes says things that indicate that she's suspicious of other people's motives. It's as if she can't automatically expect good things from them, and isn't in a position to twist their arms to get them to play nice.
Personally, I don't jump in for the kill when I see a weakness. I, like ILEs, believe in the multiplicative effect of giving everyone what they want, and maintaining equality as much as possible.
I think there are Direct Carnivores, like SLEs and some LSEs who will use force of will to get their way, and then there are Contract Carnivores, like LIEs and LSIs, who will use contracts and legal structures to get their way.
*I've always done this. I was surprised when my tri-type test gave it a name.