Oops, it doesn't look like 'outrage when greeters at retail stores use day' is a national day..

Other days

offer

Offer Day

Me Day

believe

Believe Day

kiss a ginger

Kiss A Ginger Day

Emoji Day

gallery

Gallery Day

self appreciation

Self Appreciation Day

pick me

Pick Me Day

ask out your crush

Ask Out Your Crush Day

prosecco

Prosecco Day