Not that I really care much and understand the practical reasons, but I got to thinking in beta, why does a mechanical "person" who doesn't breath need the helmet, or even just why for protection when the helmet is the same looking material as their heads. Again, I'm not bitching, I totally get it's just programming continuity across the races, but I do chuckle thinking about the absurdity. Edit: Good catch, smartphone posting and didn't proof read, thanks.
Not really. Optics, be they organic or mechanical/electrical are sensitive equipment and need to be protected. Also, as humans designed them. What their brain is is most likely in their head. So, you really want to protect what really makes you, you.