Comment by fvdessen

This is almost certainly completely wrong, the smurfs get their hat designs from the type of hats that gnomes and dwarves and goblins usually wear in germanic folklore, the most well known of all being the garden dwarves, whose design also inspired the dwarves in snow white. The design of garden dwarves is quite recent and apparently come from miners. The hats were filled with straw to protect the miner's head from the ceiling.