[watwut]

There are many professional developers who don't have side projects they would attend to regularly. Majority dont and those who do don't work on them every day.

Those I have seen to work on side projects almost every day acted similarly to people who worked long hours - eithet got burned after a while or their hourly productivity at work went down (they chatted and socialized more at work, we're more talkative during meetings, procrastinated and wasted time with play tasks instead of doing real task).