Little kids taking a shit literally wherever in China. They have special pants (NSFW?) so they can just crouch down and take to take a dump in a shopping mall, the street, the subway ...
Same for me. It was particularly vexing seeing a child pee into a plant outside an open shopping mall in the center of Shanghai. The restrooms are free, why not just take your kid inside??? The other thing that got me was people refusing to let you off the subway first before they make a mad dash looking for seats. The same happens on the elevators, but there aren't seats so that one is even more confusing.