Oops, it doesn't look like 'wear a shit hat day' is a national day..

Other days

lash

Lash Day
nail polish

Nail Polish Day
buddy

Buddy Day
hiv awareness

Hiv Awareness Day
boy friend

Boy Friend Day
youth

Youth Day
offer

Offer Day
ride the wind

Ride The Wind Day
boba

Boba Day
pumpkin

Pumpkin Day