Actually they are not the lucky ones. They are fed on their mothers milk until they are old enough to eat solid foods. When they are raised to provide milk they are kept pregnant and kept in very small pens where they can not turn around in most cases. When their milk production goes down they are slaughtered. So they are not the lucky ones.
Free range eggs are still part of the horror. Male chicks are slaughtered because they only want females. Males can not lay eggs. Like the cows, the hens also have very small cages. Even the free range chickens are slaughtered when their egg production drops.
It would be nice to have all cows freed but that is not going to happen. For that reason there would be no need to have the cows kept until death. As people stop consuming dairy the demand goes down and thus the number of cows decrease. They just keep slaughtering those cows that are not needed.