video chat

what's the deal with the video chats in the big bang theory? why do people turn sideways while talking to characters as if they were actually sitting before them instead of from a laptop screen.. for example while Amy's mom was video chatting with Amy and Sheldon, Amy's mom had to turn to her extreme right to talk to Sheldon.. i mean unless Amy's mom had a larger than life laptop/computer monitor she wouldn't have to do that.. right?