There are a number of daily events in the sun and moon demo:
1: Guy outside the pokecenter: October 19th – has an item to give to the player
2. Girl beside the Melemele Ferry Terminal Roadsign: October 23rd – is waiting for someone (”strong and cool”) who helped her after spraining her ankle.
3. Man inside Kau’oli City Hall: October 30th – his pikachu is having a birthday and is wondering who will come to celebrate
4. Police officer at the Marina: November 5th – has information suggesting a shady deal will be occurring at his location.
5.Girl inside the Ferry Terminal: November 11th – is setting sail but is afraid of boats and is a bit nervous.
A. The girl at the coffee shop mentions that the owner will be back in a month (which would be launch day Nov.18, so it is probably referring to the full game)
Items obtained from the sun and moon demo can be transferred to the full version (Greninja can also be transferred), so it is worth checking out the events.