This is how Lua got started - its predecessors started out as data description or configuration languages. The users felt it would be useful to have some forms of flow control, which led to the birth of Lua.
Indeed, I wrote a console-based mail-client inspired by mutt but with Lua for the configuration file.
The Lua code made it easy to configure things such as the path to sendmail, and your email address. But also writing functions to filter, colour, and display messages was a joy.
mutt is awesome, but the configuration language it uses is a mess of history. No loops and conditionals being somewhat limiting. People end up writing "profiles" by essentially reading the configuration values from a different init-file. Horrid.
The whole story can be found here: https://www.lua.org/history.html