By default everyone except the users group has special permissions regarding the program files folder. This includes the following groups: CREATOR OWNER, SYSTEM, Administrators, and TrustedInstaller.
If you look at the advanced security settings, you will see the the permission entries for the program files folder and a separate entry for subfolders and files. Double click the entry to find what the individual permissions are.
The administrators group has full control over subfolders and files in the program files folder by default.