Your post seems confused.
There's nothing in a net neutrality demand that would change Google's costs as such. One might argue that neutrality might impact Google's potential profits - but since Google already has such a large portion of the net's traffic, it's main business model has involved a neutral net and they have been a strong advocate. Since they profit from a large portion of Internet traffic, their aim has been to increase this traffic to thus increase their profits (IE, the ability to shake-down Netflix is not worth anywhere as much as the other ways Google makes money - see: "world's largest advertising company").
On the other hand, some of their motive for entering the ISP business has been make sure the current operators respect net neutrality and don't engaging in sleazy that exploit their monopoly (throttling, ad-substitution, etc). If net neutrality were guaranteed, Google might feel less urgency in entering this business. On the other hand, they aren't doing this at a loss so they may well continue.
Also, Google has a vast internal network that carries it's internal traffic. This network isn't part of the Internet at all and won't be affected ever by net neutrality issues.