I really feel for you. I've been getting requests to take roosters all summer, it's quite a dilemma for families that have grown attached to their birds. Everyone would like to find a place where their pet can live out his life on a farm and not get killed just because he's the wrong gender and can't produce eggs.
That doesn't happen much and I feel obligated to tell anyone dropping off a rooster to me that he will be dead and eaten within a few days. Sometimes I think I should run a "rescue service" where I tell people I find good homes for them, then take them out back and dispatch them humanely. It would just be a little "white lie" and make some people very grateful. But the "adult" in me says that this is a harsh reality that people (even some kids) should not be shielded from. We take on a responsibility with any pet and anyone who has ever had their beloved pet put to sleep knows that taking that responsibility involves bad outcomes (for us, as the ones left behind) as well. I know the circumstances here are different, but a humane death is ok, IMO. Every chicken dies someday, this is just early and painless, and not all the alternative deaths are painless.
You could try selling them on Craigslist. If you list them for free, you pretty much assure then a trip to the freezer. I have sold a few roosters as breeders, but honestly it's a long shot.
Hearing of this and without judgement is helpful. Thank you! My ears are open if anyone has ideas.