What would you do if you had 4 hours to burn at KLIA while waiting for your flight at 4:00am? Some would read a book at the on-site restaurants while breakfast, others would sit on the floor rearranging the contents of their luggage. I would personally recommend going to a Starbucks if you're stuck in KLIA at 4:00am. At any time of the day, you'll see families, businessmen and businesswomen, backpackers and others, flocking to Starbucks for their wake-up call.
My go-to coffee has always been and will always be an iced Americano with an extra shot. Caffeine lovers would disagree with me and say, "Why would you go to Starbucks? They're overpriced and the coffee isn't brewed right." I'd tell them, "Don't talk to me unless I've had my coffee. Whether it's from Starbucks, a Kopitiam or a modern cafe, coffee is coffee. It gets the job done - Waking me up."
Sometimes, I do agree with them when they tell me the coffee at Starbucks is overpriced and isn't brewed correctly. But after drinking half a cup of the coffee, it doesn't bother me anymore. I get cranky without my daily dose of caffeine so when I see a Starbucks at KLIA, I go for it. Like tradition, people have certain routines before catching their flights - saying goodbye to every piece of furniture in the house, baking a cake the night before, triple checking your luggage before locking it for the fifth time and the list goes on. My tradition, so happens to be : Get to a Starbucks after checking-in.