If "Loosh" is energy, then you are correct.

Instilling fear in a human being causes them to lose control of their energy. That energy can be eaten or absorbed by any creature so inclined.

Vampires do not suck blood. That is a concept invented by primitive people who did not have modern technology to tell them about energy. Those primitive people wanted to tell others that Vampires were sucking something important from them, something so important it could kill them, so they chose blood because every human being no matter what culture they are from knows that if you lose blood, it is very very bad for you.

Vampires suck energy. They can do it from a distance. They do not have to have physical contact. Vampires are always depicted as sucking blood from the neck because the energy of the body is very strong in the neck area. That is the only connection between the energy generating torso and the head, so the neck could be visualized as a trough full of energy flowing like water up to the head.

A Vampire can suck energy from a human being from anywhere. But if they can get right up to the neck where there is "an open trough of energy", then why not take the easy route and suck the energy out of the neck instead of working harder and sucking less energy from a distance?