They may not be as lean and have more fat (not good - especially with venison). Little to no animal predators and set up feeding stations = less exercise = more fat.
You've lost me Discern. Are you talkin' about the collared deer or the fat guys on the Huntin' shows? Are you talkin' pen raised collared deer behind high fences or wild deer collared for biological study? If you're talkin' about the latter, please explain.