[pan69]

I was unable to find this in the Fuel guide but I think Fuel uses a cascading file-system similar to that of Kohana:

http://kohanaframework.org/3.0/guide/kohana/files

[lastkarrde]

Seems pretty lazy... it would be trivial to change the autoloader to check a Controller namespace/directory.

[pan69]

It has nothing to do with laziness. It allows you to override any part of the system without actually changing any of the core framework or module files.