> yes, even their paying customers

This was the thread on Webmasterword, when Google closed Million USD Adwords advertiser accounts without warning, after changing their guidelines unannounced http://www.webmasterworld.com/google_adwords/4020049.htm

Google is completely automated, and individual customers don't exist, only statistically significant numbers.

> Self host. Don't rely on Google.

Or any other company if you don't have a contract that legally protects your data while it is on another company's server.