Because for Apple, Cupertino is the center of the universe, and they don't try to hide it. That's their time zone and that's all they really care about.
Apple tends to reuse trademarks. San Francisco was the name of a "wacky" ransom note looking font on old Macs. Likewise, "SuperDrive" was repurposed for both the 1.4 MB floppy drive and the CD/DVD-R/RW/+R optical disc drive they used to ship.
