How is it possible to get electric shock upon touching rails of an escalator? I was wearing a pair of well insulated/thick-soled shoes, when I touched the rails of an escalator (which was wrapped/covered with probably insulating material which looked like a glossy rubber) and got an electric shock. I do see explanations that static electricity might have built up on me or the rails which got a path to discharge through ground, but I don't see how is it possible since there was insulator on both the ends (the rails and my shoes).  Also, I am pretty sure NO other part of my body (like knee or an elbow) was in contact with the ground directly or indirectly.    
 A: 
I do see explanations that static electricity might have built up on
  me or the rails which got a path to discharge through ground ... Also, I am pretty sure NO other part of my body (like knee or an elbow) was in contact with the ground directly or indirectly. 

First, based on your responses to other questions, it does appear you experienced a static discharge. For that to occur you, or the object you touched, had to acquire net electric charge. 
If I understand your question correctly, is that you ask how it was possible to receive a static discharge when neither you, nor also perhaps the rail, were apparently directly or indirectly in contact with earth ground.
I emphasize "earth" because "grounding" need not involve a path to earth. Discharge by "grounding" can simply involve the transfer of electrons between an object and another object of substantial size. In this sense the "ground" is simply an object that serves as a seemingly infinite reservoir of electrons so that it is capable of transferring electrons to or receiving electrons from a charged object to neutralize the object. Such a "ground" is not necessarily connected to earth.
Hope this helps. 
