Config data strategy, auto-gen code or read in?

I am a C++ developer that usually works projects with lots of configuration data. Most projects I have been on simply read in the config data. However I have seen people create Perl and Python scripts to auto-generate C++ from the config data. They tell management they are auto generating their code and it sounds smart. Personally I like reading in the config data better. What is the best practice? What are the pros and cons?