Ideas
A night at the cinema
Show times do not bend, so lock the shared time first.
A film is an inexpensive meeting, but the show is chosen by the clock. Agree on the evening first, then pick a film that is still playing.
For a larger group, buy seats on the same row. If someone comes straight from work, pick a later show.
Add the cinema name and address to the Sopisiko place fields. The confirmation and the calendar booking keep late people in check.