Two months after the launch of Forza Motorsport 6, developer Turn 10 has added a microtransaction system to its Xbox One-exclusive racing game.

The system introduces tokens, which can be bought from the game's marketplace and then exchanged for cars - or for blind packs of 'mods', the game-altering cards that can be used in Forza 6's single-player modes.

The introduction of tokens will raise some eyebrows because it was done somewhat on the quiet (announced in a footnote of a weekly blog on Friday, enabled over the weekend), two months after the game's launch, and after Forza Motorsport 5 attracted severe criticism from fans and reviewers for its microtransaction system.

In fact, the Forza series has form for the stealth introduction of microtransactions; last December, tokens were added to Playground Games' superb open-world spin-off Forza Horizon 2, again a couple of months after the game launched without them.

Tokens' back-door route into the last two Forza games looks sneaky, and from a PR perspective it has certainly enabled Forza spokespeople to confidently, if disingenuously, dismiss the issue when asked about it prior to launch. But the caution is understandable. The implementation of microtransactions in Forza Motorsport 5 was hugely unpopular; they were aggressively priced, and worse, the regular in-game economy wasn't properly insulated from them. The comparatively meagre payouts from playing the game as normal seemed tuned to push players into spending extra. All this in a full-price game supported with regular add-on packs and a season pass.

The token system now present in Forza Motorsport 6 (and Horizon 2) is nothing like as egregious. In fact, it's very similar to the system which appeared, without significant complaint from the community, in Forza Motorsport 4 and the first Horizon on Xbox 360.

Tokens are available in packs costing from £0.79 for 100 to £64.99 for 20,000. 100 tokens will buy you a superior mod pack or a couple of modest cars (the Abarth 500 costs 45 tokens). An exotic race car like the Audi R18 will set you back 3001 tokens - somewhere between £10 or £20 depending what rate you buy the tokens at.

Importantly, Forza 6 is generous enough with credits and prize cars that it's entirely possible to ignore the token system. On the face of it, the mod packs might seem like an open play for your real-world cash, but they too are easy to ignore - the game's economy isn't tuned in such a way as to encourage using their minor boosts or debuffs, and driving purists won't want to anyway. You can even turn tokens off, so you'll never see the option to spend or buy them. You don't get more discreet than that.

So, nothing to see here? In gameplay terms, nope - tokens, as they have appeared in four out of the last five Forza games, are an inoffensive extra revenue stream for the developers that presumably fulfils a need for some players. It's only their surreptitious introduction that rankles, really. Turn 10 needn't be so ashamed of them in future.