Restaurants also can have a number of tables pre-allocated to third party companies on the assumption someone can book them though that third party. Similar to

Restaurants also can have a number of tables pre-allocated to third party companies on the assumption someone can book them though that third party. Similar to this, I once tried to stay in a hotel by just showing up to the reception desk. They told me they were fully booked. I then found the same hotel on a booking website, booked it on there, showed the hotel my now 'reserved' room then stayed at the hotel the same night.