Answer is yes. That's called ghost power or phantom power. These happens in cases where you switch off TV or music system or set to box with remote control. Also when you just shutdown a PC without turning off the switch or just plug in chargers but not connected to anything with switch in On.
Today there are many devices fall under this category, even manufacturers make them to reduce power consumption in stand by mode. But it's not zero. They consume a bit of power ranging from approximately 0.1W to 2W depending on system. These are consumed by standby house keeping system which runs clock, ready to power on, wake on circuits, retention cicuits etc.
For one TV or PC it's negligible but nowadays considering a TV, PC, STB, one or two mobile chargers, laptop chargers in a home. The wastage can be about 1-2W. Consider a apartment, there may be >100sW being wasted. There are places where these wastage really matter and electricity is scarce. These places can be lighted with 100s of 2W LED bulbs.