walking around on a rug

Today, I was walking around the mall with my brother and sister to grab a bite to eat. When I'm lazy, I tend to drag my feet when walking. Suddenly, my brother bumped into and we both felt a shock! What could it be other than static electricity! Because the mall is air-conditioned, the air is less humid and there is more likely for static electricity to occur in an environment that has less water molecules in the air. Dragging my feet on the carpet at the mall caused friction and my body gained electrons! With all these factors in the mall, how could one NOT shock someone at the mall? After the first shock, my brother and I started to see who could shock the other person more. Unfortunately, we had to leave the mall, and outside we couldn't shock each other. I guess we couldn't build up static electricity outside because it was more humid. Shocking, isn't it?