No, they'd just have superior writing. If you can't make a threat credible, you change the threat to ensure that it is.
Left 4 Dead dealt with this nicely. The horde isn't a huge issue for those already immune and armed with weapons, but the super-zombies are dangerous, especially if you're alone. Plus, the virus is airborne, the zombies are fast, etc. The vast majority (90%) of the population was infected by this and turned early. Of the remaining 10%, nine percent are turned by scratches, bites, and bile, something anyone who has played the game can tell you is commonplace.
This is a credible threat. Within a matter of hours, a given city would be overrun, and, while a military response might be powerful enough to overcome it, there's no guarantee. Vast amounts of military personnel will likely have turned, there'll be chaos and disarray...
In short, L4D has a credible zombie apocalypse scenario. I prefer the slow-moving, headshot-only zombies myself, but I still love L4D and it shows that thought went into this.