"Don't worry. The moral choice will be a reasonably good option, and a cartoonishly evil option that doesn't really make sense to do. Because that's how morality works."

I'm parodying the Fable games, here, but the game that really opened up my eyes to moral choice possibility in games was Fallout 3. Prior to that, I thought the ability to be good or evil was ground breaking, when what was more accurate was that I simply hadn't played many RPGs before that weren't Final Fantasy or Dragon Quest.

Here's one early example of something that happens in Fallout 3: You live in an underground vault, protected from the wasteland above that exists after an apocalypse nearly two centuries ago. Something happens when you're 19, however, and now you have to escape from the vault because the people in charge are out to get you.

On your way out, your childhood bully runs up to, asking for help. There are giant bugs on the loose, and they're attacking his mother. He could take out the bugs himself (they're not so big they can't be stomped), but he's terrified of them, and is desperately asking you to save his mom.

As mentioned, this guy bullied you as a child. He potentially stole a sweet roll from you on your tenth birthday, bullied you and your best friend, and it's implied he's beaten you up in the past.

Your options are to save his mother yourself, refuse to help and ignore him, refuse to help and attack him, attack him before he even initiates dialogue with you, run and try to avoid talking to him at all, go and attack his mom instead of saving her, try and convince him to go back and save his mother himself, offer up your baseball bat or BB gun so he'll find his courage and go save his mom, and for any of the options in which you convince him to go back and save his own mother, you don't have to go with him. You can help or observe if you want, but you can just send him back and just be on your way.

Granted, you could argue that boils down to "help", "don't help", or "actively make worse", but that's still one more option than games that boil things down to "good or bad" will usually give.