I have never once read a EULA - I don't really see how you could make it all the way through one and stay away. How important is the EULA/Terms and conditions

I have never once read a EULA - I don't really see how you could make it all the way through one and stay away. How important is the EULA/Terms and conditions that you always have to click OK to when you register to use a new web app? If I was to release an app without legally prepared terms and conditions would that be a stupid thing to do?