Not only CALEA, but telecoms, ISPs, and other providers work hand in hand with governments who request data, whether those requests are via NSLs, warrants, subpoenas, court orders or just government employees asking nicely for the data.

Many companies, including for example Apple who is open about this, are happy to hand over private information via simple requests from law enforcement that they are not legally bound to respond to like they are with warrants or subpoenas.

I'd assume by scratching law enforcement's back, the government scratches compliant companies' backs, as well, considering the contracts they get and favorable treatment they get from regulators.