D3218HN, power button is broken

We have a D3218HN monitor that was purchased less than a year ago and is still under warranty. The monitor power button has become disconnected from the unit and the monitor is in a powered ON state. The only way to power the unit off is to unplug it. Dell support has told me that this is apparently not considered a hardware issue and is not covered under warranty as it's considered basic wear and tear. I am failing to see how this is not covered. It is a piece of hardware connected to the monitor and critical to being able to power the monitor on and off. Right now the internal mechanism is stuck in an ON state so at least the monitor is useable. But from what I am being told if it was stuck in the OFF state Dell would just tell me 'oh well that's just wear and tear'. What's the point of the warranty?? This is pretty terrible workmanship!