This way you won't have to chmod the device file. If you want to customize X applications globally, put your customizations in those files. They are marked as configuration files, so their contents will be preserved during upgrades.
Every distribution seems to have a different boot-up method.
Tell me about Debian's. Like all Unices, Debian boots up by executing the program init . Any scripts in the latter directory are usually reserved for system administrator use, and using them in packages is deprecated. The two-digit number following the 'K' or 'S' indicates the order in which the script is run. Lower numbered scripts are executed first.