Largely based upon the fact that GuP isn't a guro manga. Ribbon no Musha in particular shows characters falling out of their tank and having it roll over on top of them, and nobody seems to actually get injured or killed from this.
In real life, commanders would pop out of their tanks to get a better view of the battlefield, but they would largely do this because the view from inside the tank was pretty awful otherwise, and they weren't exactly being shot at at all times. Even in tank-to-tank shelling at range, the odds of the individual person being hit was relatively low (the tank's much larger, after all, and less than half the person sticks out). Also, unlike GuP indestructible tanks, you very much could die if inside a tank that took a shot, anyway. The basic calculation is that popping out of the hatch to actually be able to see the threats to you and react to them entails an acceptable risk compared to the risk that you let a tank blast you broadside because you didn't see it coming sitting buttoned up. Again, this risk is very much skewed by the indestructible nature of GuP tanks, and it kind of reinforces the Nishizumi Stupid Evil concept that it's perfectly fine to kill off schoolchildren in pursuit of what's basically a hobby.
If they were under fire from small arms or a machine gun (like with Anzio, later), however, they'd be a suicidal idiot not to duck back in the tank and close the hatch.
No, not that. I mean you, Erika...Don't worry, the tank interior is coated with a special carbon, so it's completely safe!Erika, that was dangerous, y'know!But you say this is completely safe,based on what?Huh!?
