A Reddit user posted a photo of black scabs on their roosters, combs, wattles, faces, and asked a fair question: if it were mites or disease, wouldn't the hens have it too? Only the three roosters are affected. That's a sharp observation, and it points away from the usual suspects. Our take? This looks like the aftermath of a rooster rumble, and we're not just clucking for the sake of it.
Let's be honest: roosters fight. It's what they do when there's more than one and not enough space, ladies, or clear hierarchy. Three roosters in a flock of 18 is a recipe for some fowl play. The scabs are concentrated on the parts they use to spar, combs and wattles are prime targets for a peck or a spur. Mites and diseases don't typically discriminate by gender unless there's a specific vector, and the OP's logic is sound: if it were contagious, the hens would be scratching too. Fighting explains why only the boys are marked up.
Practical terms: separate your roosters or give them more room to avoid each other. A single rooster can handle a flock that size just fine. The other two might need their own bachelor pad, or a new home. Scabs from fighting usually heal on their own if the wounds stay clean, but keep an eye out for infection. Swelling, pus, or lethargy means it's time for a vet visit. If you're worried about mites, check the hens and the coop for tiny crawlers. But the pattern here screams "scuffle," not "scourge."
What we'd tell a reader who asked us: You're not chickening out by assuming the worst, but your gut is probably right. Watch the boys for a few days. If the scabs dry up and no new ones appear, it's a territorial tiff. If they spread or the hens start scabbing, then you pivot. Keep your flock safe, but don't lose sleep over a few battle scars. Sometimes the answer is simpler than we fear, and a lot less creepy-crawly.