Firstly I would like to explain what a virtual state is. A virtual state is a state which copies something from a real state: constitution, economy, army etc.
The most famous virtual state is Sealand placed in the waters of the Northen sea 10 kilometres away from the British shore on a former air defense platform: "Roughs Tower". Although Sealand is going to be 50 years on the second September this year this country already had a revolution, has a government abroad and a monetary authority! There are only 18 inhabitants, but this country is famous all around the world. 
So is a virtual state only a game? Sometimes yes, sometimes not it depends on what you want it to be. Sometimes it can very profitable. For example since 2012 Sealand is a tourist attraction. This country also makes some money by selling souvenir coins, made of silver and bronze, and post stamps.
Sealand also sells its email addresses and ID cards.
In my opinion a virtual state can bring money if you want it to, if you do not, it can be a nice game.