Why does Samsung include useless capacitors?
There are four comments on this reddit thread that may be on to something:

By silver_pc:


  could it be a form of 'paper towns' on maps - AKA fictitious
  entry to identify direct copies?


By toybuilder:


  Not that they are necessarily doing this, but I've heard it said that
  mass manufacturers will keep removing capacitors until their product
  stop working.  (Certainly, it was common to see PC motherboards with
  unpopulated decoupling cap pads all over the place back when I used to
  hand-build PCs.)
  
  If you have a mass-production setup to stuff boards and do automated
  visual quality inspection, maybe you don't want to take the downtime
  hit to reprogram your production line as you introduce and monitor
  ongoing production changes with the ultimate goal of removing the
  capacitors.  If so, you could nullify the capacitors by stuffing them
  as before, but with both pads on the same plane.
  
  Samsung manufactures capacitors, so maybe they're a bit more willing
  to burn through a short run of boards with wasted capacitors if, in
  the long run, they can more definitively get rid of them.
  
  Keep in mind that large companies like Samsung have the ability to
  test their products for certification purposes in-house, so it's
  probably cheap enough to run a small batch to test and accept/reject. 
  And if accepted, to just release it into the market.
  
  At least, that would be my guess.


By John_Barlycorn:


  I believe this has more to do with manufacturing process than it has
  to do with electrical purpose. Modern electronics manufacturing is
  bat-shit insane with regard to speed.
  
  We're talking about robotic movements that are so fast, that air
  resistance and machine vibration have to be considered.
  
  The position of parts that feed the pick and place machines is
  critical to the speed of operation. So they spend a lot of time on
  setup. Then press "Start" and watch her whirl. So if they end up with
  2 products that are similar, they have to go through this expensive
  setup change run by an expensive engineer to switch them out. But
  these caps are so cheap that after you consider this setup change, it
  might actually cost them more money to remove them during different
  runs. They might just say "Fuck it" and let them populate them despite
  not needing them.
  
  My father worked in the industry for years, and had some experience in
  smaller volume stuff. In manufacturing this sort of backwards logic is
  not uncommon. You do what's cheapest/most profitable which is not
  always the least wasteful option.


By CopperNickus:


  There are other planes in a tablet: the display and case. Maybe the
  answer lies in the third dimension. Might there be a brush/spring
  contact or some other connection on another layer of the device that
  completes a circuit when the tablet is assembled? That technique is
  used in their cellphones to mate various internal boards to the back
  and case.
  
  In the phones, it's spring contacts mating to gold or silver contacts
  when the device is assembled.
  https://i.imgur.com/ztOZmDN.png
  
  Or perhaps just some proximity based RF control related to the
  display?