Cryptocurrencies generally are considered an investment in the financial world though. The two things they are generally classed as are investments or a form of currency (in reality they are both but some people will class them as only one or the other). They certainly aren't a game though. Investing in them is uncertain so you could say investing in them is a "gamble" but something being uncertain / being a "gamble" is not the same as it being a game and cryptocurrencies do not meet the basic definition of a game.
A college degree is considered an investment too. Does this mean we should have the right to sue all colleges who put us deep into debt via college loans etc? After all, we could make the claim of false advertising, scam, etc, just as some people say about the gaming business.
My point is, yes you can go with that angle but to be lawsuit happy only brings greater lawsuit risk for all parties. Lawyers benefit of course when everyone is suing everyone but the industry suffers because innovation becomes much more costly.
I'm going to say I agree that from an ethical point of view perhaps the DrugWars team messed up. They did not consider the impact their decisions could have on the sentiment of their customers/players. Player sentiment in my opinion should come before all.
If they can find a way to profit in a way where the players share in the success as stakeholders then I'd be okay with it. Drugwars in my opinion should also become an SMT and support the Steem ecosystem but the exact economics in my opinion need to be negotiated with the community. The team needs to understand that a loyal fanbase can allow future games to inherit the same players (player loyalty) in the same way Blizzard for example did with World of Warcraft from the Starcraft, Diablo and other fanbases.