Such a heavy duty tripod is typically referred to as a camera pedestal.
The wheels can be rotated for turns or locked in a parallel position to track in a straight line across the studio floor. Further, they can be set and locked to trace a circle around a distant centre of rotation. They can be unlocked but control of three independent, freely revolving wheel makes smooth operation a challenge. As you mentioned, holding a shot when live, is easier if you frame, lock to hold the shot, unlock to reframe. It had to be done smoothly and the friction locks could be adjusted to accommodate this easily.
(We television camera operators would have contests to see who could negotiate an obstacle course in the studio made with folding chairs and lighting stands. Points deducted for poor framing, less than smooth movement, and slow timing, etc.)
Some had housings for use in a studio context and some were able to collapse for easier transport for field locations and used minus the trucks in a fixed position.