In some games there is a Gambling skill. For any gambling game with any amount of actual skill, there's no problem. A person with a Gambling skill of 16 is more likely to win at poker than a person with Gambling skill of 13.

But in some of those games you can use this skill (in character) to influence the outcomes of games of pure chance. A person with a Gambling skill of 16 is more likely to win a coin toss, or at a slot machine, than a person with Gambling skill of 13.

In some sense, this may be justifiable. If the game is cinematic and plays loose with the laws of probability, for example. If you're playing James Bond, you damn well should have a better chance at winning at roulette or craps than some random shmuck off the street. So don't dismiss it as entirely silly.

Transcript

Chewbacca: All of these interesting shenanigans with flying and gunning and so forth are a little ancillary to the central conundrum. I can only fix the hyperdrive with the power off.
Han: I'm an awesome gunner! And pilot! I'll do both, you can watch.
Leia: If it's possible for one person to do both, then I think I do have an idea...
Han: Flip you for it. Call!
Leia: <sigh> Heads.
Han: Okay, Dex roll... 1.
GM: The coin falls through a crack in the deck. There's a crackle of sparks and a whiff of burnt wiring.
[SFX]: szzzzt!! szzzzt!!
C-3PO: Why are you making a Dex roll for a coin flip?!
[SFX]: kpow!! szzzzt!!
Han: I didn't want to leave it to chance!