One of my favorite thrillers is
The Day of the Jackal and the main character travels around Europe staying in luxury hotels in 1963 (The Hotel Amigo in Brussels) is one and eating at luxury restaurants (Seven Nations in Brussels, Cunningham's in London). At one point he needs to make a long distance telephone call and Forsyth writes:
As he usually did when he needed something done, he walked into the most expensive hotel and asked for the concierge