Google Chrome is bundled with a lot of freeware apps and the user needs to uncheck a checkbox to avoid it being installed as a default browser. That's literally how it got current market share, along with being heavily advertised on google.com.
Makes sense, and works well with my experience that users don't really care or know what they are using. If the extent of customization is your bookmarks, being converted to a happy chrome user isn't hard. If it's more than that, a coerced install is probably not going to make you switch.
But for most people, they won't really notice a difference between Chrome and Firefox in their daily usage.
