Probably lecturing the choir, but I'll do it anyway.
You may have noticed with prior pre-season scouts of public lands, but most animals really change their patterns just before the season opens.
I suspect it's all the guys showing up a few days early and tearing up the country on "scouts," but doing little more than driving off the game.
Best advice I got as a young man still serves today:
Read the terrain and decide where the game is likely to move once the pressure is on. Then on opening day, start about 3 hours before daylight with a flashlight and move quietly into the new country and wait for the action to start. Usually takes around 30-45 minutes for the spooked game to arrive in the new location, but the smart old ones got there days ago and need your respect while waiting for light.