So the old dude survived not by wits but being in a shelter, left because he feared for her daughter future and was unprepared to the zombies outside, but whatever was in the shelter was worse, he lived for revenge as it made him turn away from the fact that running away did kill his family.
I can only imagine the shelter having everybody under control 24/7 and the leader/s deciding the life development of every refugee, dude didn't want hsi daughter forced to go with someone.