The English verb “to bust” (unconnected with the noun “bust”, which refers to a woman’s bosom or a sculpture of a person’s head and shoulders) is American slang for “to break.” (But in a military context it means “to demote” and in a police context it means “to arrest.”)
According to the Online Etymological Dictionary, “to bust” is a variant of “to burst”, in use since 1764. “The verb sense of ‘to burst’ is first attested 1806…”
A “doorbuster” refers to a sale where products are offered at bargain prices. The idea is that buyers would be willing to break down doors and burst (or to bust) into the store to buy the products on sale at discounted prices.
A variant of a “doorbuster sale” is an “early bird sale.” This derives from the proverb “The early bird catches the worm.”
In Los Angeles, where I live, parking in a public parking lot can be very costly, unless you park early enough and leave early enough to enjoy an “early-bird” price.
Other expressions with “bird”:
a bird in the hand is worth two in the bush
birds of a feather flock together
to eat like a bird
a little bird told me
a bird of ill omen
a bird of passage
the birds and the bees
for the birds
“Black Friday”, in the context of consumerism, refers to the beginning of the Christmas shopping season in the United States, at the end of November. On Black Friday retailers open their doors very early in the morning and offer discounted prices.
The following video clip shows a Black Friday stampede by shoppers.
Bird Words: Colorful Expressions Using the Word "Bird"
Black Friday (shopping)