There was a fence corner on a sheep ranch where I used to snare coyotes for the rancher. Laying close to the crawl with the snare were at least 30 coyotes in all conditions from fresh to skeleton and the action never slowed down. They cared not for their fallen comrades.
I didn’t say they cared for their comrades but I am surprised that they weren’t smarter about your snare. They are usually pretty smart about dangers. Maybe the difference is that hanging a coyote on a fence is intended to warn them off and be seen from a distance whereas you were setting snares with the intention of luring them in. Did you bait the snares?