ESTA replaced the previous I-94W form; in fact most of the questions are the same. You could also be denied entry before ESTA was introduced.
The best rendition of the text on the I-94W form is undoubtedly Frank Zappa and the Ensemble Modern's: https://www.youtube.com/watch?v=qPPDrXHjJx8
I'm not sure exactly how we're getting away with having this ESTA thing at all for countries that are supposedly part of the Visa Waiver program, without them retaliating in kind. I only hope that we'll come to our senses and stop before they do so. But given that ESTA has now existed for 10 years and both parties seem to support it, I have low hopes of it going away.