Why snowmen are usually decorated with pipe?

Frosty the Snowman
The Ronettes

LYRICS
Frosty the snowman
Was a jolly happy soul,
With a CORNCOB PIPE and a button nose
And two eyes made out of coal.
Frosty the snowman is a fairy tale, they say,
He was made of snow
But the children know
How he came to life one day.
There must have been some magic in that
Old silk hat they found.
For when they placed it on his head
He began to dance around.
O, Frosty the snowman
Was alive as he could be,
And the children say he could laugh
And play just the same as you and me.
He led them down the streets of town
Right to…

Pipes used to be as common as hats. Now they are about equally rare, but still remembered in traditions.