Small-Arms vs passengers

[Eternal]

I always wondered why the passengers on the tank get defense.
If I correctly understand the rule, the attack goes like this:
- The attacker rolls a die, adds his attack to the value. Then the defender rolls the die and adds the lowest armor of the tank to the value and the terrain modifier to the value.
But then we have a strange situation, the passengers on the "Tigre" get better protection than in the bunker (the Tiger has lowest armor 4). But this is not realistic.
Is not it better if the passengers on the tanks do not get protection from shooting at all?
Or even vice versa will receive a negative modifier, since they are on armor and easy to hit on them?

 

[Barthheart]

Part of the "protection" that is factored in is the amount of balls/guts it takes for the attacker to fire at a tank in hopes of hitting the riders. Firing anything at a tank usually results in the tank firing back. So don't think of the defense as just "something to hide behind" other factors come into play sometimes.

 

[Nick DelCorpo]

I don't think you should get the lowest armor but rather a modifier for moving perhaps. The tank will fire back as its action or part of OF.