Earlier quoted context omitted.
Doubt it was a factor with Bezos. The guy is rich enough to live anywhere, and has houses everywhere, as you also observed. Somehow the office didn't land in Beverly Hills or the Texas ranch. I expect the fact that he already has homes in NYC and DC is related to the fact they are in fact important locations for his business.
Most CEOs are rich enough to move. But they are also powerful enough to get the company to move to a location more convenient or appealing to them.
The office in NYC is going to be nothing more than a big satellite office compared to the huge HQ in Seattle, so it's not like he's actually moving Amazon's HQ and himself to NYC. In fact I doubt he'd spend that much time there. Given his duties, he'll probably be in Seattle most of the time.
Also, I very much doubt the office in DC is there because Bezos is just dying to spend more time in DC ;-)