"Why shouldn't we eat eggs when the hens lay them anyway?"
"Eating eggs is not killing chickens."
We can separate this problem into two parts. The first concerns the mass production of eggs, and the second concerns the domestic production of eggs.
Mass production of eggs
Large egg farms, whose products are mostly found on the shelves of small and large stores, keep their hens in terrible conditions. Maybe these conditions meet the rules of some state agencies, but I wouldn't say that they have an iota of concern in them. Apart from the concern for profit.
Chickens are often kept in cages, they don't move, they get sick, infections spread. If they're not in cages, then they're on the floor, but the story is mostly the same - thousands crammed into a small space. There is no need to waste words on the food of these animals - it is loaded with antibiotics and hormones to make the yield as high as possible. When infection occurs, all chickens are killed. There was a situation in Croatia recently, when 150,000 chickens infected with salmonella were killed.
Domestic production of eggs
Ok, and what if the chickens are kept at home, in the backyard, are free, eat worms, grass and corn?
Let's dive a little deeper.
Did you know that wild hens naturally lay only 10 to 12 eggs per year? It takes about 25 hours for a hen to create one egg, and this process is quite exhausting - one of the numbers that tells about this is that the hen withdraws 10% of its calcium reserves from bones to form the shell of one egg.
Imagine if the chickens that people keep in their backyards only laid so many eggs. What is the benefit of them? You feed them for nothing. That's why chicken are often given 'supplements' in their food - hormonal preparations to make them lay more eggs.
Another interesting fact: have you ever wondered why are eggs a symbol of Easter? Well, that's because hens naturally don't lay eggs in the fall and winter. Only in spring, when it gets warmer and the days get longer, hens start laying their first eggs. Once upon a time, when we had not yet modified everything, people looked forward to those first eggs, celebrated and decorated them just in time for Easter. It seems that we have left the tradition with us - but we have forgotten its origin. Today's hens are so modified and pumped with hormones that they simply keep laying eggs all the time.
That's why we don't eat eggs.