Oops, it doesn't look like 'Hamburger MonthAnd Hamburger day' is a national day..

Other days

coffee

Coffee Day

nail polish

Nail Polish Day

fiancee

Fiancee Day

pick me

Pick Me Day

offer

Offer Day

stud

Stud Day

carpenters

Carpenters Day

chocolate milkshake

Chocolate Milkshake Day

my little pony

My Little Pony Day

Me Day