it’s a model that works for some of the largest service providers on the web (and STW of course). Doesn’t mean it’s some kind of nefarious plot.
No, but it is always worth questioning motivations and how they plan to make money from this venture.
STW, for example, it is pretty clear how the forum makes them money (or pays for itself at least). People pay for Premier accounts, or get adverts, plus it increases the draw of the site and hopefully the readership.
The VPN is less obvious. Unless they plan to insert adverts then how will they make money? Presumably by selling data they gather.
That doesn’t stop it being a good deal – just go in with your eyes open.