So for the rest of the year, say my insomnia shows up and I've been awake since 8 AM the previous day, I go to work anyway. I get maybe two hours of work done all day, but I sit at my desk and that's apparently what's important. That's only happened once this year, but it was Monday this week so it's fresh in my mind.
It's stupid. But I've got one sick day left and I might need it worse come flu season.
There are plenty of things I like about my job, but our time off policy is not among them... In the tech industry I'm guessing this is less common because it's not easy to hire good programmers. In other industries, I doubt it's an unusual experience.