It will. But using power from a wind turbine is still better than a gas/coal plant.

The gas would probably be extracted either way. And that requires power. But it'll be worse if the required power comes from more gas instead of wind or something else that's non-polluting.

This way, at least the overall emissions is reduced. So, for example, if the total emissions had 10-20% due to the gas used to create the electricity/power for the processing, at least there will a 10-20% reduction in the total emissions.