Which Is a Better Way of Obtaining Scales, Gaussian Blur or Down Sampling?
Down sampling may discard relevant features, while blurring should not.

As a toy example, a down sample may remove a pixel which is a local maxima, while a blur operation will preserve the maxima by increasing the values of nearby pixels. If the local maxima corresponds to an interesting feature, it may still be discernible by the human eye after blurring.

From a computational sense, Laplacian pyramids are able to reconstruct an image precisely because a blur-subtract operation preserves the "information" in the scene.