Google wanted to create a browser to promote web standards and practices. As a company whose largest properties can exist largely on the web for many it's important to them that the browser, wherever it be located, can be expected to do the things they want it to.
Through Chrome push for adoption of whatever they want. webM, HTML5 audio/video, increasing JS performance expectations, hardware acceleration or access, etc. Not saying these are things that came individually from Google but with control of the browser they can make a push for things that work for their products and needs.