Differences for me aren't based on week/end, but on intended use. I don't normally carry anything bigger than a 3.5" blade outside of wilderness and sporting situations (Large Senenza, GW, etc.) so that would not be an issue at the office - if I had an office anymore.
One tendency I do have is to carry a stouter knife if I know I'm going to be poking into things. That does not necessarily mean a larger knife, though. Sometimes I'll carry two knives for that reason.
Maybe should mention that I am an architect, so I work with both paper and building materials. A relatively pointy knife with a very sharp edge is super useful for working with paper, sharpening pencils, etc. Something more along the lines of a .20" GW is more useful for jobsite visits, where there is sometimes some poking any prying involved - or just tasks that you wouldn't want to perform with a very fine edge.
Ironically, some of my smaller knives are fixed blades. Something along the lines of a Busse Bear Cub will take a fine enough edge to work with paper and yet be stout enough for prying out heavier staples.