What happened to play from CD?

I remember, time was, you bought a computer game, popped the CD in, copied the executables over and then played the game. All the data stayed on the CD and you didn't use up your whole hard drive. These days, every game demands that you install the complete contents of the CD/DVD to your hard drive and it pisses me off. It's not like it needs to be copied to the hard drive, I've seen the very same games run on consoles without hard drives to install to and my computer has a faster DVD drive than most consoles. It just annoys me to have the number of games I can play at a given time limited by the fact that they all demand to exist on a CD/DVD and my computer, especially considering they all demand that you have the CD/DVD in the drive while you play the game.