Why can't static classes have non-static methods and variables?

Question

Why can\'t static classes have non-static methods and variables when non-static classes can have static methods and variables?

What is the advantage of having static

Answer 1

Static class can't contain non-static members because by definition it can't be instantiated so there's no possibility to use these members.

However, static members in non-static class can be used without having class instance - a bit different scenario, i.e. for utility methods or factory methods.