Labor Day is an American holiday to celebrate working people and their contributions. It was born out of the organized labor movement, specifically the Pullman Strike in 1894. The original meaning of the holiday is often overlooked in the 21st century, but it used to be the main focus of Labor Day, as you can see in 16 vintage photos of the celebration at mental_floss. Shown here is a union float from a Labor Day parade in 1909, and a community barbecue from 1940. Link
Big business is full of corruption, and we still have it. Politics is full of corruption, and we still have it. Labor unions were formed to give some of that corrupting power to the workers, and we did away with most of that, at least here in the U.S.
Some of them spent most of their time in luxury funded by the workers and extorting money from the employers.
It just became a protection racket.