During one of my chicken obsessed phases I would read the forums at Backyard Chickens. One way to deal with roosters, kill them. As soon as you realize your chickens are male, and you know you can't keep them, 'dispatch' or 'cull' them from the flock. If you don't want to dispatch them, find someone who will.
For some people, chickens, hens particularly, are pets who lay eggs. And they wouldn't imagine eating their pets. However, pets are put down too.
Roosters in this case are given the same treatment thoughtless cat owners give to their pets when they can't, won't take care of them anymore, by just putting them out and hoping for the best. 'The best' has just as much chance happening as winning a lottery. We know what happens to former indoor cats who are tossed out into the world, they get run over, they go hungry, they get beat up by feral cats. Why would a rooster fare better?
Let me end with a story. When I was a preteen, I had chickens. Due to possums, accidents, aggressive fire ants killing poults in their sleep and other mysterious predators, my flock of twelve chicks became just 1 grown hen and 1 grown rooster. These were free range birds who wandered our yard, and our block. One day the rooster came up missing. Due to the large feathers we found, we figured one of the neighborhood dogs got hold of him, an unpleasant end. Animals deserve a painless end. Turning a chicken into someone's dinner seems to be a fair option too.