VANCOUVER – When Mitchell Demeter and Jackson Warren opened the world's first bitcoin ATM at a coffee shop in Vancouver, it was an instant success. People actually lined up to use the machine, which processed about $1 million in digital currency transactions over its first month.

But one day in November, a few weeks after launching the ATM, Demeter noticed something peculiar as he perused the machine's transaction data at his office, across town from the coffee shop. At one point, the machine had voided 15 transactions in a row, for no obvious reason. So he drove down to the cafe, and as he walked through the front door, he immediately saw the problem.

A man was sitting next to the machine, at one of the cafe's wooden tables, and he was holding a sign that read: "Don't Pay Transaction Fees." This very human entrepreneur, you see, was undercutting the world's first bitcoin ATM. As people walked in to use the machine – which was charging a 7 percent transaction fee – he offered to exchange their money, by hand, at a lower rate.

>A man was sitting next to the machine, at one of the cafe's wooden tables, and he was holding a sign that read: "Don't Pay Transaction Fees."

Demeter booted this enterprising entrepreneur, and now, he posts his own man next to the bitcoin ATM – not only to protect the machine from such competitors, but to ensure that people can use the machine without problems. It's a typical bitcoin story. It shows that although this digital currency is maturing, it's still very much a wild west. There are countless holes in the vast system that is bitcoin, and so many people are looking to exploit them, both online and off.

To protect his ATM, Demeter hired a guy named Cameron Gray. A musician and former healthcare technician, Gray puts in a few days at week beside the machine, which operates during cafe hours – from 9am to 9pm on weekdays. He earns $12 per hour, in Canadian dollars. But there's a big perk: He can convert his cash into bitcoins for free.

He's also getting an invaluable education in bitcoin from the several dozen people he talks to each day. "I would do this job for free strictly for the wealth of knowledge I've gained from sharing info with people," he says. "I'm trying my best to stay on the cutting edge of blockchain technology as it evolves."

Cameron Gray (left) helps Kavanveer Dhiman buy a bitcoin at the ATM. LIFE Magazine recently released a collection of unpublished photos from the battle of Anzia in Italy, taken by photographer George Silk. Photo by George Silk

In addition to guarding against entrepreneurs trying to undercut the ATM, Gray helps people set up and manage their bitcoin wallets, the software you use to send and receive bitcoins. He also helps reassure them when their bitcoin buys don't go through instantly.

That's what happened to Kavanveer Dhiman, a University of British Columbia Student who stopped by the cafe to buy a bitcoin on a recent Sunday. His transaction, it turned out, had been queued but not processed by BitStamp, the bitcoin exchange that does the back-end work for the Vancouver ATM. After speaking with Gray, Dhiman was reassured that he'd eventually get his bitcoin, and he went on his way.

>Now, when someone stops to chat with Cameron Gray, he steers them toward Cointrader, which charges just a 0.5 percent transaction fee.

So far, Cameron Gray's salary seems to be one of the costs of doing business with the Bitcoin ATM, which is still processing between 20,000 Canadian dollars (about US$18,000) and 25,000 per day. "We were surprised that there's a lot more to it than setting up and letting it go."

But Demeter and Warren have actually taken a page from that fee-slashing entrepreneur. They've moved their offices into the cafe's meeting rooms, and they're using the ATM as a lead generator for their next line of business – a full-fledged bitcoin exchange called Cointrader. Now, when someone stops to chat with Cameron Gray, he steers them toward Cointrader, which charges just a 0.5 percent transaction fee.

Demeter and Warren plan to open a second ATM in Calgary soon, followed by one in Singapore. The ATM is built by Nevada's Robocoin, a startup company that hopes to bring the machines to major cities across North America and plans to open its first U.S. ATM over the next few days. Each machine costs $19,000 – human not included.