I boot my desktop at most every hundred days. The boot process could take 10 minutes (it doesn't) and I wouldn't give a damn. Of course, I run Linux. It simply doesn't require periodic reboots. I pretty much only restart on installation of a new kernel, and that is just my own paranoia. With a properly designed system, the time it takes to reboot is immaterial. I've noticed that it is mostly windows users who talk about reboot times.
I know people that like to shut their computer off when they are done. Not just put it into sleep mode.