While I grew up on a farm and hunted since I was .... 6?...... and it is hard for me to understand getting emotional about these things that just must BE ....... try to frame it this way: They are chickens. They were created for this. Meat birds were made to be eaten. DP breeds as well, after they outlive ther usefulness as egg producers or breed stock ..... you are the farmer, on however smal or large a scale, and your job is to husband your land and animals ..... to have them be the best whatever they can be ..... let them get to the top of their game, to be all they can be, and that's it ....... to do otherwise would be a disservice to the breed. Conserve the desired traits, and make food from the rest.
With regard to meat birds: Think about it this way: You bought or hatched them because they would make weight fast..... many generations of these birds' lineage were striving to produce what it is that they are now ..... it IS why they exist, at all...... don't dishonor that. They are now all they can be, at the top of their game. If that's not what you want..... buy or hatch something else next go round .....