I'll be the odd one out, as a relatively new Linux gamer. I almost never shut it down unless I want OS updates. Weeks without an intentional shutdown usually.

I treat it more like a phone than I do a TV or radio like I saw other people mentioning. Always on, as I left it, running whatever it was running. Screen turns off after 30 minutes of course.

I don't pay for power, so that's not really a concern for me, and I use it frequently enough when home that most of my time involves the desktop in some way.