It's that age old analog vs digital sound discussion. Digital virtual instruments are limited by the range of the soundcard output. An analog system does not have these same limitations. And the age old debate is that the things done to sound outside our range of hearing actually change the sound that we hear. Which is why people tend to feel analog sounds are "warm", and capture something that cannot be replicated by a digital emulator.
I used to be like you myself, and honestly I do use VST's + hardsynths. I like to use broken/flawed sounds to get my feeling across. But I do recognize the limitations of my gear and attempt to place things in such a way that they accent each other and work together to form a solid dynamic range. But truth be told, get the best VST synth and an old analog beast side by side through an amp. The analog is going to produce a solid frequency from one end of the audio spectrum to the other. The VST or VA Synth is going to get artifacts or degrading tones somewhere along the line. This is usually compensated for with FX or added volume, end result being audio fatigue in my opinion.
You also are correct, most bands just hit the preset engine and let it fly, never understanding the depths that any one synth can go.
`michael