Every config file becomes something close to a scripting language at some point. Build files, video game maps, etc.
Eg. You have a game with enemies spawning in some circumstance. The file that defines the level of the game now needs a bit of logic to specify that the enemy spawns given conditions. If you don't use a scripting language you'll have a field in that file that takes parameters for the conditions. Now do this 1000 times over for all the other little things you may want in the level. Pretty soon your file that defines the level is slowly becoming a shitty adhoc scripting language.
Eg. You have a game with enemies spawning in some circumstance. The file that defines the level of the game now needs a bit of logic to specify that the enemy spawns given conditions. If you don't use a scripting language you'll have a field in that file that takes parameters for the conditions. Now do this 1000 times over for all the other little things you may want in the level. Pretty soon your file that defines the level is slowly becoming a shitty adhoc scripting language.