As I said they have "natural" rush to kill  ;D.

In that case, they would just kill a person and move on, they wouldn't eat them (like we saw in movies).

They just like it I guess btw have you seen zombies dying of starvation in any movie ? ;) I watched in few of them when they told what I told you, something like "they were living underground for 10 years or more and they haven't eaten anything"  I guess they just like our meat :).