The same temperature is far less tolerable indoors than out. Particularly in modern buildings, which are designed for total reliance on central air systems and so don't have organic airflow. (Which also has advantages, mostly better use of space; but it introduces a pretty hard dependency on operating in those buildings for long.)
People installing utilities in residential buildings (e.g HVAC technician), people in non-air conditioned kitchens (and especially dish-washing rooms), automotive/equipment techs and many others often deal with similar environments. Working outside in the sun sucks just as much, arguably more if you have to wear a lot of PPE.
The difference is, people in those situations get breaks (by law), and they also get to leave when their shift is over.