Both your previous definition of cheating and this new one about "fraud" imply other players. You can't defraud yourself.

As for lying online, I can do that without modifying the save game. I can edit screenshots with paint, or just make any claim I want. And if the community is aware that the save file is editable, any exaggerated claims will be viewed skeptically anyway. If you have an online leaderboard then that's a different issue, but then we're outside the single-player, offline game scenario.

Finally, about the EULA, if you're making your own game I don't see why the EULAs of other games should matter. It's your game, license it for use however you want.

It sounds like you are trying to justify it, and that's fine because it's your opinion. I guess it's difficult for me to empathize with you because I have never felt an impulse to search for a save directory and edit the file to enjoy a game. In fact, I had never heard of save editing before reading this topic. Um, by the way, those are not my definitions. I quoted a dictionary on both occasions for clarification.

I don't understand why the developer should be concerned with what kind of gameplay the user wants to draw from the product when it breaks away from the original save file design.

The user has paid for the game, it's done.
The developer has (supposedly) done his job in providing the game in its original design.

As long as the user does not breach my copyright in some way (extracting my graphic and audio assets and reselling, distributing or incorporating them into his own projects, and also piracy), then I don't mind in the slightest how much he tinkers with the game files.
I would even go as far as adding a "Make sure to backup before making changes" Easter-egg comment inside the game configuration or save files.

Simply put, if a player wants to manipulate save data, they will find a way. If they are a programmer, they will find a way to make a program to allow it and then just put it out online to let other players do so. Though,I think the best way to counter that is to entice them with a bigger bribe. Make the game moddable so that they can add weapons or levels or characters etc. so the game always feels fresh.