Cygwin Contradiction

Java is used as a crossplatform programming language and Ant is the defacto standard build tool for Java projects. So, why are there so many Java projects out there that use Ant, yet still require a Unix like environment to build? Since I currently run Windows due to requirements within my business, I am baffled why I NEED Cygwin to emulate a Unix envirnoment to work with a Java project?

I agree with most developers that I talk with that using a tool like Cygwin does make development easier, but the concept that it should be required is absolutely ridiculous. The additional layer of complexity introduced by running yet another operating system, harms and does not help the adoption of many projects.