Pasteurized honey is very similar chemically to invert syrup but has proteins, pollen, and other peculiar characters added through the bee digestive process that sugar water won't have.
The processed bee nectar is more expensive but really achieves the same ends in a finished beer that invert does - added aroma, flavors, and color. What I'd really like to do is heat up and caramelize some honey as a beer adjunct one of these days with some beer wort mixed in. It would add some malt dextrins into the mix that way.
We always have a container of honey in the house, but since I'm lazy, most times I just add the honey to the wort for an ABV boost and dryness to spare myself some extra effort.