Why can't they just use regularly slotted or Philips on something like this?
Simple--they don't want people to be able to repair it.
TORX isn't much of a deterrent anymore, even the ones with the center pin can be found at the orange and blue box stores.
The tamper-resistant screws nowadays have triangular or 5-sided socket heads, or a 2-hole "spanner" type of drive arrangement. Then there are the ones that are ramped so they drive in with a standard slotted driver, but cannot be backed out without heroic measures like vise-grips.
