Perhaps I'm missing something here, but what's the issue?
I'll admit, I'm not familiar with Resident Evil Mercenaries. But, the practical impact aside, this is hard to read as anything but a dick move. Sometimes people like to start stuff over, even if it's a simple matter of wiping high scores, and they shouldn't have to purposefully corrupt their files to make that happen. Assume for the sake of argument that there are no "points of no return" in the game, everything can be revisited, and all user-entry is forever able to be edited. So what? The same is true of Super Mario World, that doesn't mean nobody ever restarts it. It could be as simple as one day wanting to "earn" everything over again. As a matter of progression, structure, and satisfaction. People do that. And I know Mercenaries 3D does have skills and abilities to be unlocked, if nothing else.
The real question, though, is not "What was lost?" It's, "What was gained?" What is the purpose, either to the player or to Capcom, of a single permanent save, with no alternate slots and an inability to clear?
Capcom, in doing this, is asking for a leap of faith that their game will accommodate all possible desires of restarting without the need to actually do so. That is an extremely lofty promise given that we're talking about what often amounts to personal preference. I restart many supposedly replayable games, Punch-Out!! and a variety of Mario titles among them. So, why, Capcom? What's the tradeoff? To us? To you? To the game balance? If they cannot answer that, then they are asking for a risk, even if it amounts to only a minor annoyance, with nothing to be gained. That is senseless, and it's no wonder they'll catch [parasitic bomb] for it.
I don't much care because I don't follow Resident Evil. But it strikes me as a supplier trying to exercise undue control over how a consumer uses their product after they've purchased it. Generally not something they have any business doing, so I can sympathize.
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