Ah, that's rich. It's true until A) there's any sort of disagreement or B) StreetEasy doesn't hit whatever revenue targets that Zillow sets for them. Might be weeks, might be months, might even be years. But there is no world in which Zillow owns StreetEasy but doesn't impose any changes on them.
Of course, with any acquisition, changes happen eventually. This isn't like Yahoo buying a company for patents or talent and quickly shuttering the product, or HP/Oracle buying a company and killing it under the burden of largecorp bureaucracy. We're talking about a pretty small company, buying another startup.
See also: http://hotpads.com, http://agentfolio.com, http://mortech.com which were all acquired within the last year by Zillow. a few "a Zillow business" logos here and there, but if you were a customer of those companies before the acquisition, you would probably say Zillow has left them alone.
disclosure: i have no insider info
