Seriously though, it's harder to avoid in startups, and this forum is more or less dedicated to startups, so I'd expect quiet a few people here do land in this boat. I'd also guess side projects that involve programming probably count as work, as far as what the author intended, and everyone here has side projects going.
Keep in mind that there are plenty of managers that subconsciously reward extra time, and plenty of workers that will put in a little extra to get ahead. It's not fair or good for work/life balance, but it happens. Drawing your own hard line is a good thing, and nobody should be expected to put in unpaid time, but sadly it doesn't work the same for everyone everywhere, and being too vocal about extra work can have unintended consequences.