You can certainly shrink or scale things this way but it is not likely to give you the result that you would hope for. Consider something like the following, a metal path abutting to a metal pin shape:
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Which is then shrunk or scaled, you might get the following:
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The shapes may no longer abut or connect because they have both shrunk or been scaled in place. This is what VLM takes care of, moving things so that the relative placements stay as originally intended. As you may realise, this is not a trivial operation, hence there is a tool for it (and of course other third-party tools exist too).
I hope that this answers your question.