"When you arrive in those swish American hotels, they look at your shoes," my business-travelling friend warned me, "then they know." Just from your footwear they decide which room to give you, where to seat you in the restaurant and most importantly, they know how much you're going to tip.
This is a worry, since we're booked in to the Waldorf Astoria, rated Chicago's finest hotel by Conde Nast and TripAdvisor, and I have only one pair of shoes with me.
My wife's feet will pass muster. Her simple yet elegant buckle-ups pair effortlessly with her black and white outfit by a leading Australian designer. But my shoes are a dead giveaway. They've been my travelling companions for three years and are equally comfortable hiking the Indonesian jungle or cycling through Belgian drizzle.
My shoes seamlessly match my quick-dry trousers and superfine merino shirt that can be worn for a week without stinking. Anyone can see my shoes are new to five-star luxury adventures.
Three young, impeccably suited doorpersons greet us as we clatter our cases past the fountain in the cobbled Waldorf Astoria courtyard. We've walked two kilometres north from the downtown station, pretending we were "getting the feel of Chicago". Really we were saving a cab fare.
Our bags are spirited from our hands, doors are held open, while a message is whispered into a hand-held radio. I suspect it's: "Shoe alert, main entrance!"