Fluff Vs WYSIWIG: Where to draw the line.

So, i was thinking yesterday. Where should we draw the line with fluff Vs WYSIWYG, I mean I don't know any marine players that put grenades on all of their models which is to the meanest of rules lawyers against WYSIWYG (same with both bolt pistols and bolters on ever model) but they are not for fluff reasons but for ease.