Mr Schlappig became hooked on loyalty programmes aged 15, when he realised that a strategic choice of flights around his native US could earn hefty rewards, the New York Post reported.
Now 25, he's visited 50 countries and travelled 5 million miles - the equivalent to flying round the world 125 times.
"My philosophy is always to earn and burn," he told the New York Post.
His smart planning isn't restricted to flights. He used a promotion which offered a free night in any Hyatt hotel after paying for two nights to his advantage.
"My local Hyatt [in Tampa] was $80 a night, and the Grand Hyatt or Park Hyatt in Sydney or Tokyo was $800 to $1000. You were spending $160 to get a night at a $1000 hotel."
The New York Post reported that Schlappig now runs a business called PointsPros, which teaches others how to make the most out of airline loyalty points.
He also runs a blog called One Mile At A Time, which chronicles his journeys , aviation news and tips and tricks for holiday bargains.
"As much as I love planes, they're a means to an end," he said. "The goal of all of this is to see new places."
The well-travelled Schlappig told the New York Post the South Island is one of his favourite places he's visited.
He also said he will have to stop what he's doing eventually.
"I don't want to be 65 and traveling nonstop, alone. That doesn't sound fulfilling. At some point, I would love a house and a dog and to be in a relationship."