The Resident Evil series is supposed to be cheeky like that and therefore works with its terrible acting and dialogue. It's a parody of thousands of terrible horror films we've seen over the years (check out some Ed Wood films sometime if you haven't already).
There are only a handful of A-list voice actors out there but many actors have shown themselves quite capable of voice acting and doing it well. It shouldn't be hard to pull down some B-level movie talent to video games, at least for the main characters. It would be loads better than what we currently have now (just look at Heavenly Sword, the biggest name in that game was Andy Serkis, though to be fair, the guy is an amazing voice actor and absolutely nailed the Bohan character).
I think the problem with video games is that they refuse to grow up. The same developers who found anime fun and exciting as children grew up physically but remained loyal to the often bad and terribly cliched stories they loved as children. Given the geek nature of the business, very little is done to expand upon the simple "shoot 'em up/spout terrible one-liners" story arcs that games have been subject to since their inception. Gameplay has matured a great deal, as has music, but plot lines and dialogue are still almost as bad as they were 15 years ago.
Which is why gaming won't be taken seriously as an art form (excepting a few notable games from people like Will Wright or Team ICO) until it forces itself to grow up a little and truly challenge the medium as a vehicle for great storytelling.
Edit: I saw you added another paragraph. I agree with you. But what seems odd to me is that so much of gaming has evolved while this one aspect is still fuckin' terrible by anyone's standards. I hope we will see real writers start taking on video game plotlines and dialogue but I just don't see it happening anytime soon. I think that's one of the last things game directors will want to give up because it's probably one of the aspects they enjoy most (complete and total control over dialogue and story basically makes the game yours).

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