Any campus (i.e. universities, hospitals, Sprint headquarters in overland park, KS, etc.) environment usually has such tunnels. The reason being that it is much more effecient to operate the HVAC systems from a central location. Many campus environments ,such as Truman State University, purposefully place these tunnels along the same paths as the above ground sidewalks thus melting any snow accumulation during the winter.
During my undergrad at SIU (which by the way covers over 1100 acres compared to UT's 350 acre campus that is "one of the largest in the world" according to the story...typical Texan) I worked for physical services which administers these tunnels and used them extensively during inclimate weather. We actually found drums of supplies from the cuban missile crisis (first aid, food, water purification, etc.) that nobody ever bothered to haul back out!