Google presentations use gender of viewers

I got this Google messge, as a step to listen to some technical lectures:

I consent to provide Google with information about my gender to help Google understand the diversity of the I/O audience, improve content for I/O presentations and events, and develop I/O presentations and events that are of interest to the audience.

Huhh? How is tht going to work?

I normlly would not mind giving my gender to Google, but now that I know that it intends to use info about my gender to alter the content of some technical lectures, I think that I would be contributing to an evil plot. Besides, doesn't Google know this info anyway? It is not a secret.