Earlier quoted context omitted.
Well, Apple makes most money with hardware. Unlike Google who makes most money with ads. So at least in theory Apple can more easily invest in privacy. EDIT: Check their last quarter's results, Apple makes only 6% of their revenue with online services: https://www.apple.com/pr/pdf/q1fy15datasum.pdf
There was a reddit post where OP works for a third party company that Apple send Siri voice to. People complained that users didn't read the EULA or whatever. Anyway OP said it was very specific too and crazy. So it doesn't sound like Apple being the champion of privacy.
Apple is using third parties to help make Siri better not to make money.
And let's be clear we don't know the contract between Apple and these companies. Given Apple's track record it should have numerous privacy conditions.