Thanksgiving - Black Friday

Thanksgiving was first celebrated in 1621 when the pilgrims invited the Native Americans to celebrate the harvest.
It is celebrated every year on the 4th Thursday of November. The familys stay together, give thanks for everything and have a typical thanksgiving meal. They eat for example turkeys, match potatoes, green beans, corn pudding.

The day after Thanksgiving is called Black Friday. It's the start of the Christmas shopping season. The shops open at 5 o'clock in the morning and grant discounts up to 50 %. People queue up the whole night to be the first to go into the shop.
I don't understand why they are doing this. I'm glad Black Friday isn't common in Austria.