Call centers aren't really offices, though. They look like this:

http://www.savalinews.com/wp-content/uploads/2016/11/Call-Ce...

Which look very similar to this:

https://s-media-cache-ak0.pinimg.com/originals/d4/84/2b/d484...

The main difference is the machine is a calling machine instead of a sewing machine.

Call centers are more like call mills, and those people are definitely wearing shirts with blue collars.