Oh yes, these Chi Sao competitions are so weird. Chi Sao has nothing to do with actual fighting, it's an exercise to learn specific principles and to develop a better tactile reception. Such a competition cannot even show how good your Wing Chun is. Too many Wing Chunners focus too much on Chi Sao, because it feels good (it really does) and gives you the impression of being in control (as long as your partner, who thinks the same, stays with Chi Sao and doesn't bring other tools into the play).
As an exercise it might help to support your wrestling though.