I was browsing through the sound files in Silver and found a conversation between David and his Grandpa about some stupid thieves that were trying to rob them.

Anyone saw this scene in the game? I didn't.

I can't specify the name or where these files are at the moment since I don't have Silver installed.

It could happen when you speak with Granddad at certain points in the game. Sometimes after a scene you can talk to him once or twice more.

Sometimes developers make/record parts of the game that get scrapped later. And sometimes they don't remove all of the assets that they made, and this could be such a thing.

Just to name another example: in Symphony of the Night there is an audio file that was supposedly used in a cutscene that never made it into the final game. The audio however, still exists and via tools this was discovered.

Yes, it could be that :)

I searched the internet and found nothing about such scene in Silver.