Aaagh, what kind of birds are those??!!??
OMG I can’t believe what these people eat in other countries!!! YUCK!!!!
They are most likely chicken chicks- old enough to be sexed as roosters and culled.
There are always 50% males hatched but you don’t need roosters to get eggs for eating. You only need roosters if you want fertile eggs for hatching, and even then you only need 1 rooster per 12- 14 hens, and too many roosters/hens will result in injured birds because roosters fight.
So wherever there is a poultry hatchery, in the US or in China, there is a problem of what to do with the extra roosters because they are impractical to raise in mass for meat due to the fighting. It’s easier just to hatch twice as many birds as needed and just keep the females. Some males can be caponized [neutered] and then raised for meat but that takes extra time, skill and labor, but the usual thing was and maybe still is to toss the males in a chick chopper and sell it to a renderer to turn into pet food.