People don't need a keypad because they have the digits row. But there are languages (in Europe) which reuse the digits row for extra letters (which don't even fit there) so you have to press shift to enter a digit (yes, you can't enter such a letter in capital without using CapsLock), unless you have a kaypad.
People don't need F-keys (so these can be reused for multimedia controls) because they are not techies. Insert for the same reason.
People don't use Delete/Home/End/PgUp/PgDn because they are completely uneducated about the basics of using a computer and use mouse/touchpad, arrows and backspace instead. Believe it or not, I've met people who don't even know Ctrl+C/V (let alone Ctrl+X or Ctrl+Z) and would always use the right-click menu (which even requires an additional keyboard key to be held pressed on a Mac) to copy/paste anything.
This said, compact keyboards target anglophone non-techie users (or hardcore VIM fans who have ways to do everything without leaving the home row).