Well yeah, obviously. It surprises me that an idea as basic as this is newsworthy. Could someone please fill me in on what people thought was playing a larger role than this?
Many people find it more convenient to instead believe the difference is caused by people in charge automatically offering women less than what they would offer a man. Of course, studies controlling for the type of job, credentials, experience, ability, etc., show that to be a poor hypothesis, but it is nevertheless a phrasing that makes it easy to make people angry (and vote for you).