ummm it's 365 days in a year btw 😀
For one thing, people can justify the price cause it doesn't cost a whole lot to keep your machine going. It's harder on the machine (ie. hard drives, cpu, etc.) to keep starting and stopping the machine cause they will wear out and get stressed out faster than by leaving it on(Hot and cold and running from a dead stop is not good, it's like keeping a car running, how much gas is saved if you will be back in it in like 2 mins). Alot of people use their machine at various times of the day, not all at once and then turn it off, in which case it's better to leave it on. Alot of people run a server and have to leave them on.
If I know that I am not going to use my machine for the rest of the day, then I turn it off, if not I leave it on. That's just me though cause I am not running my server right now.