Oops, it doesn't look like 'park like an asshole day' is a national day..

Other days

law

Law Day
brow

Brow Day
self appreciation

Self Appreciation Day
slime

Slime Day
artists

Artists Day
bounce

Bounce Day
ride the wind

Ride The Wind Day
boba

Boba Day
boy friend

Boy Friend Day
gum

Gum Day