I've started wood-gluing together my IKEA and other flat-pack furniture to try and increase its usable life since - as you said - it's counterproductive to dis/re-assemble most of it anyways. I've not been at it long enough to claim effectiveness, but so far nothing has started to wobble.
Even the cheapest cardboard-filled IKEA units hold together much better when glued, and makes moving the units less stressful (no more "it's creaking / skewed when I pick it up").
I do the same. I don’t plan to take it apart but wood glue is part of any woodworking shop and I don’t see why assembling Ikea should be qualitatively different. I want my assemblies to stay together, not vibrate, to feel sound. Gluing joints is fundamental.
