The idea is that service providers that provide gigabit internet benefit, as an incentive to build out gigabit internet. So Comcast offers gigabit internet (actually 2 gbps) at an outrageous price, just so they can qualify for the tax break. While the article says it's meant for Google Fiber, it is clearly for any provider who wants to start providing fast internet to people. This would all be fine if the tax break was for companies providing gigabit internet for under a certain price.