I have 4 vampires and aside from accidentally hitting the feed button when I meant to do something else, none of them have fed in over 2 years. And when I fed accidentally I immediately slotted a vampire skill and spammed it until I was stage 4 again.
I wish there was more of a trade off so you actually had to make a decision that made a difference, but sadly there isn't much point to bring anything less than stage 4 unless you're RPing or something.