[buwaya]

Many armies through history have had similar sorts of things among junior officers. In the British army regimental “mess games” could get rough. The games they played in school and on leave were rougher. The Germans, as students, slashed at each other with sabres, looking to acquire scars.
Male bonding rituals are often rough.
This business of the pillows is mild.

[bert]

-——This business of the pillows is mild.——

the pillows are perhaps a downgrade from some other form of fighting in the past

[agere_contra]

The Germans, as students, slashed at each other with sabres, looking to acquire scars.

That's right. They wore special body armor that exposed only the 'safe' parts of the face.

Their male bonding ritual was bound about with rules. If you broke them then you went to jail or were executed.