Agree totally with all those saying that cheap chicken -including that used in millions of ready meals and takeaways - is a scandal.
Knew a chap some time ago - big, strong, born and bred rural (so not squeamish) - who resigned after just a few days loading chickens from a very big and well-known producer/breeder on to lorries for slaughter. He could not bear to see the suffering.
Other have already said how the poor birds' lives before that are hellish.
I used to keep chickens.They are lively, affectionate, very individual creatures. If you look after them well, they provide delicious eggs for most of the year, and come to know you and rely on you. They are much easier to keep and care for than a dog, for example.
I am also old enough to remember how a carefully raised chicken, roasted, was a real, real treat. Just a few times per year. Other meat was also a luxury. We ate very well, however, and were healthy. My parents died recently; both around 90 years old. Eating some decent meat and a lot of veg, bread, pulses did them no harm.
Generations have been raised since then to think that we have some sort of right to cheap meat, no matter what suffering is entailed. That's an abomination.