I have been a nurse for a long time. I routinely left the hospital with more pens than I brought in with me. This was not due to deliberate theft. Just, pens get left laying around, and I pick them up habitually. If a pen is on the floor, it is mine. Left on the pyxis /med dispense machine, mine. In the charting room with no obvious owner, mine.
I square up my karma by freely giving pens away to anyone in need. "Oh, you lost your pen? Here, take one of mine." I have reunited many pens with their proper owners in this way. But still, I have several little pen piles around my home. Even if I immediately stopped my pen redistributing ways, I expect that I will never need to buy a pen, ever, for the rest of my career.
Now, mechanical pencils. Those I have some preferences about. Give me my sharpwrite 0.7mm over any pen, anyday.