They have banking people (who use a largely entirely different technology stack, budget, and way of working), and people who have worked for smaller companies, but they don't have a huge number of veterans of large consumer webapps. Google's NYC office probably is more of a sink than a source for ops talent, and there isn't a large presence of declining big giants to strip for engineers like there is in Silicon Valley.
Do people move from SF/SV to NYC to work for established companies? I could see this if you had personal reasons for wanting to move (being from NYC and going back, or just wanting to go there), but it doesn't seem like a compelling option otherwise.