Tim - do you genuinely believe nobody would get mashed in the face? If so our club must be very unlucky!
I've seen (and received) a few nasty knocks from the ball.
2 plastic Albions have had a ball go through the gap between the grille and the peak, one from a seamer resulting 2 black eyes and a sore nose, and one from a spinner which resulted in one black eye.
Our keeper was stood up wearing an old Masuri, the batsman edged one and bang, broken nose through the grille!
I've seen 2 broken noses in the nets from medium pace bowlers being top edged into faces, and myself top edged an incrediball (remember these are so soft colts face them with no pads!) into my lip and split it during a training session.
As for fielding I've been hit on the head twice, once resulting in blood and a bruised skull! Also seen 2 split foreheads and a fractured cheekbone from fielding, so should we wear a helmet at all times on the cricket pitch?
I guess my point is if you chose to wear a lid or not is up to you, but in a game with a hard ball travelling at high speeds incidents are always going to happen.