Oops, it doesn't look like 'fast food fast day' is a national day..

Other days

youth

Youth Day
hot chocolate

Hot Chocolate Day
camera

Camera Day
boy friend

Boy Friend Day
martini

Martini Day
boba

Boba Day
lisp

Lisp Day
cat girl

Cat Girl Day
kiss a brunette

Kiss A Brunette Day
nae nae

Nae Nae Day