Hey guys did you knew that when you are not playing the game your survivors will still be searching for some loot and can die? rest in peace my Maya :(.
You can tell them to stay at the base! That's what I did. When I started playing today, everyone was happy and with high morale (Albeit there was much less food in the base!)
How do you tell them to stay?
Of course you need to have enough resources, or they'll make a run for it to get some before running out. If you do, you can always tell them to cook something or create something at the base. That make them busy until you come to play again.