One of my children has a ThinkCentre for space-saving reasons.
The built-in camera is switched off in the BIOS (and access to the BIOS is password-protected). I don't really want a teenager having a camera on the PC in their bedroom.
The camera also has a physical cover that can be slid across, so one always has the option of blanking it if it is enabled - beats draping a blanket over it!
SD