Having been a free-range egg farmer I feel particularly strongly about the subject, and find the "cheap food" argument nonsensical. Have one free-range egg instead of two battery eggs if cost is really a true concern -usually the people who buy battery eggs also buy vast quantities of processed "convenience" foods at very premium prices as well.......
Firstly it is undoubtedly cruel - all of their instincts are denied - to scratch, to dust-bath - even to stretch, and often spend their miserable lives crammed into cages with other birds, standing for their entire lives on metal rods - kept in overheated conditions (keeps feed conversion rates high) - beaks trimmed to stop them pecking each other, and fed a "diet" direct from the bowels of hell........ broad-spectrum antibiotics (to keep them alive in the atrocious conditions), coccidiostats (to keep the worm burden "manageable"), whatever protein is cheapest on the world markets at that particular time (these days often GM), DPM (dried poultry manure) -much of the high protein food "goes straight through", so is collected, dried, and added to the feed......... then either a "straight" chemical colourant to give the yolks a "healthy" colour, or something like canthaxanthin, which is sold quite legally as "natural" despite being synthetically made, and being banned for use in salmon farming due to it's toxicity........
I wouldn't touch a battery egg on principle, let alone wanting to risk the chemical contamination - thankfully the more enlightened supermarkets are refusing to sell the damn things, and hopefully it will soon be about as acceptable as putting kids up chimneys......
Aged parent used to work in the occupational therapy department of the local
mental health establishment - there were a constant queue of people who ended up having had major breakdowns following working in a major local broiler plant - it demeans all those who take part in it, and some succumb to the evil they are required to carry out........