Yes, correctional institutions would be a good place, and anywhere you can't or are limited running UTP and fiber ....
Structured cabling can get expensive (in labor) if you've got to cut through walls and go through some difficult areas. Thinking Patch and repair of drywall, fire stopping, painting, concrete strcuture etc. . I've experienced it first hand. It ain't pretty.
Again, it is a judgment call that can make or break a deal. A "hybrid" with Mesh and Fixed may fit the bill. Designed right, it could be a dream come true.