For decoration. Same reason some armies had brass eagles, or spikes, or painted shields, or unit crests on their helmets; decoration. In Vietnam, American GI's wrote griffiti on the cloth camoflage covers which adorned their steel helmets.
By tying a scarf or some cloth on your head before wearing helmets.
stockings
Of course not, you should not eat horse hair anyway. So, I would not think they are made of horse hair.
Cuz it messes up their hair.
A Horse Shoe The logo for the Indianapolis Colts features a speed blue horse shoe.
7 out of 8 do not wear a helmet in the USA.
There are many uses of horse hair, but one is bow's for violins.
horse farm
hats,helmets,hair accessories
Stuffing hair in helmet unsafe
A baby horse is born with some hair but very little.
a clipped piece of horse hair.