NYPD does not buy more of any firearm than same gun in civilian sales. Far from it. And you did say that exactly, separate from your comment about Colt sales.
Colt started to care again recently about civilian sales once FN was allowed to make the M4 for US military sales.
Besides military only buys a few models of firearms in large qty from a few manufacturers. M4/M16A4, M9, maybe a few shotguns. No state or local PD can compete with civilian sales. Taking this stand would only affect a sales in a few NE states.
As one posted stated the civilian market is buying everything available and has shown a remarkable capacity to do so year after year of record setting sales.