A chicken has no idea what it's alternatives in terms of housing or feed are afterall, nor does a pig or a cow
Neither would we, if raised the same way from birth.
Giving an animal choice, or free will, to live as it would prefer (with all the inherent risks of injury and disease that come with it) is not necessarily a show of "anthropomorphism". It can simply come down to the belief that animals have the right to express themselves as close to how nature intended as is practically possible.
Horses, when allowed "free rein" to decide whether to work or join their herd-mates at pasture, will more often show a preference for the latter (
here), than be put under saddle. Animals have the ability to make choices, given options.
However, even the free-range, "natural" approach to farming usually has to make "unnatural" concessions - young goats and cattle are dehorned, male animals are often neutered, sexes are reared separately, etc, because living "as nature intended" can be stressful and potentially dangerous for the animals concerned.
Unfortunately, given the high demand for food to satisfy the ever-growing human population, mass production reigns, but we should to do this as ethically as possible. It just so happens that the better we manage this arrangement in terms of animal health and we!fare, the more profitable the enterprise.
There has been a ton of research on minimizing the stress on livestock during transport and slaughter. Simple things such as rounding off chutes rather than expecting animals to negotiate corners which create piling up.
We have made great strides in the design and implementation of handling facilities, thanks to Temple Grandin and others. However, I don't think we should be patting ourselves on the back just yet, especially when it comes transportation.
Although most countries now have welfare legislation in place (and not before time) with regard to rest stops, feeding and watering of animals in transit, it still isn't enough to counter the physical and mental stress on these animals during long haul journeys.
It is a shame that so many local abattoirs have closed down in favour of more profitable centralised meat processing plants, forcing farmers to send their animals much further from home than they would wish. I will refrain from recounting the too numerous preventable livestock transportation horror stories I have witnessed. We can, and should, do better.