Oops, it doesn't look like 'steak n shake day' is a national day..

Other days

lash

Lash Day
bubble bath

Bubble Bath Day
hannah

Hannah Day
ride the wind

Ride The Wind Day
girl friend

Girl Friend Day
bonang

Bonang Day
slime

Slime Day
boba

Boba Day
tell a fairytale

Tell A Fairytale Day
law

Law Day