The giraffe's neck is obviously a benefit to its species, but none of the steps needed to "evolve" that neck would be beneficial. The veins in their neck need to be able to restrict blood flow when the giraffe bends down to take a drink while at the same time, the heart needs to be strong enough to pump blood all the way to the brain. Without either of these features, a giraffe with its long neck would never survive, yet none of these features are beneficial without the long neck. The giraffe's neck is not just a neck, but an entire system of organs and features that are all worthless or even fatal without all of the required components being in place.
This is just a way your way of saying that, "I can't think of how this could have happened via the theory, therefore the theory is wrong." In this particular case it's easy to show it can occur.
Start with a creature with a short neck that eats leaves. One gets a slightly longer neck, allowing it to eat from branches that are slightly higher on the tree/bush. This may or may not be beneficial, but nor is it a detriment. Repeat over many, many generations, while similarly selecting in the other traits as necessary since, by necessity, the creature still needs to drink water.
Macroevolution is even accepted on most ID/creationist fronts -- as proof, the Creation Museum even has a display on it/i>, even if they don't call it that because that would, well, make them look even more foolish.