Pulling is a psychological act—people are always pulling vital force from each other though they do not do it consciously, i.e. with a purpose in the mind — it is instinctive in the vital to draw force from wherever it can. All contact is in fact a receiving and giving of vital forces in a small or great degree. You have yourself said that after meeting such and such person you felt empty and exhausted—that means the person drew your vital force out of you. That is what people do at pranam, instead of being quiet and receptive, they pull vitally. It can be stopped by cutting off connection, but if the Mother did that at pranam, then the pranam would be useless.
Ref: The Mother with Letters on The Mother