It's equally impractical to replace something as simple as prison bars with a forcefield device that might be susceptible to failure, or to replace something as simple as towing cable with a tractor beam that might be susceptible to failure, or to replace something as simple as wheels with a levitation system that might be susceptible to failure. It's a common conceit of science fiction to replace practical engineering with overcomplicated energy-based alternatives for the sake of seeming futuristic.
I can buy prison bars and devices that are, for the most part, stationary and hooked up to a UPS system. Such systems could give real practical advantages over their simpler counterparts.
A clothing belt, though... would be subjected to quite a lot of stress, and for little to no practical benefit over normal clothing. Replicated clothing from a fixed wall unit sounds far more practical in a Star Trek world.