You could shut down the Pi by just disconnecting the power line. Many claim however it could potentially damage the file system - or worse.
We're shuting down a lot of Pi's with simple radioshack 220v mains timers. We've done this since a couple years resulting in about 50,000 of raw unplugs and cold reboots. I still have to see the first Pi not wanting to spin up in the morning.
If you follow the book it is not the right thing to do, but the effect depends on your exact situation. What works for us might not work for you.
I do understand we're lucky.