The idea comes up a lot - that Google organic might favor sites that use this or that other Google service. There's never been any data analysis to support the idea. In addition, Google regular talks about their long term view - that it's critical to keep organic rankings free of that kind of influence. They tell us that their long term business health depends on that separation - and they're right.
I think we're so used to seeing "favored" treatment in many other areas of business in the world, and so it's natural to wonder about it in the rankings, too. But Google says no, and there's no evidence outside of small anecdotes that always evaporate into "coincidence" when looked at closely and statistically.