In just 4 panels you can tell what type of people they are

Dad just dive bombs like the escentric swimmer he is

Max is grumpy and upset, and uses the flap like a normal person. But he holds it open for his little sister, and closes it when he is done.

Zoey Is hyper and just looking around the place, not really paying attention to where she goes.

I know exactly who these people are, just by going through a counter.