I keep borrowing this person's computer, existential crisis

Often, when I'm at work, I am compelled to do at least 30 minutes of bullshit work a day. This might involve spinning in a chair, pretending to read emails, or doing these godforsaken trainings on a site that is used by my employers. Typically, I am using a computer that would be used by another one of my coworkers when they're not up front, but it's situated near that person's cubby. This is kind of an inconvenience, because I typically feel compelled to move for that person and apologize, which makes me feel awkward. I don't know if anyone else feels awkward because of my behaviors, or if I'm just assuming that they feel awkward because I feel awkward, and I'm just projecting.

Anyway, there's a computer directly below my cubby. I would be more than happy to use it, but because another one of my coworkers likes to behave as it they own the damn thing, and they're always having conversations with people on it and leaving it open, with all of their accounts signed in and shit. Even when they're not using that computer, they've got all their chat logs and emails open, and for some reason they seem to get huffy if someone else uses that computer. I'd rather not be heir to whatever sordid business they're up to on the thing, so I just use the computer closest to the door.

I nearly apologized for existing once to the coworker whose computer I am most certainly hogging, and it got me to thinking about why someone should apologize for existing. Everyone places demands on someone else due to the mere act of existing, and because of this, we are compelled to behave compassionately towards one another, feeling as we do that in some way, we owe them if not a debt of gratitude, at least an apology for existing and consuming resources that they themselves might like to consume; even the mere act of exchanging money is a type of apology, really. All ethics begin as an apology for our existence.