Its about being waterproof. You climb into the suit and you only have two openings. one for your face covered with a hat or secondary hood. the second one is in the chest covered by a rain jacket or poncho. most of the time you are hunched over forward protecting both the head and chest hole. Under heavier rain you can actively protect both openings as they are both within reach.

Its also a suit that a single person can get in and out of without any secondary help.

Its a good system that looks weird as fuck.

For the arc reactor, obviously

Whalers were really really big on belly rubs back then, they were willing to forgo a little breathing as long as they could get there belly rubs.

It’s so your alien chest burster doesn’t ruin your garment when it comes out. The work must continue, no stoppages, throw the next poor sap in the body bag.

For Kuato.

I was wondering the same thing. Maybe that's where you get in from?

Haven’t you seen total recall?

The whalers were Jaffa, obviously.

For peeing

So it doesn’t cover up the mouth.

The technical term is a Brown Waffle

X-men: Zeroth Class suit