If you actually read the article, this is just a normal-ish (although peer-to-peer, which is interesting) free VPN, it isn't actually oriented towards cheating.
The funniest part is that if the article is to be believed, the "cheating" consists of simply increasing your ping. Which... you don't really need a VPN for.
How is it possible to keep it free?
The devices of our free VPN customers are used to create a secure peer-to-peer network that our commercial clients can use to securely route their traffic via various global endpoints. As a free client, you will likely not notice any impact on your resources as that happens. The data transferred in the background will be metered by your mobile operator according to your data plan.
What does this mean? What use would "their clients" need access to your network? What are they routing to through your network and how does that help with efficiency?
Their commercial clients are doing things that give IPs bad reputation or banned from services, so they use this service to get access to home IPs to use.