I never had a problem like that. The animals I caught in legholds were calm when I found them, until they seen me. But the legholds I have, have a rubber cover on the jaws. It may hurt and hold tight but I wouldn't think it as suffering. The snares on the other hand was a fight. I'm sure it didn't last long, being strangled, but the ground and brush was always tore up from the fight. I think snares are illeagal in some states or areas, not sure on that. I'm sure death isn't pleasant however it happens. I guess those body crushing traps are the most humane (I don't know what they are called) but there is a limit on size for those I believe.
We cannot continue to do the same things and expect different results