There are two rules to follow when constructing a functional composite package:
Establish the base directory based upon where the vast majority of the package objects go.
If a package object goes into a common directory that is not the base directory (for example, /etc), specify it as an absolute path name in the prototype file.
In other words, since "relocatable" means the object can be installed anywhere and still work, no startup script run by init at boot time can be considered relocatable! While there is nothing wrong with specifying /etc/passwd as a relative path in the delivered package, there is only one place it can go.