There is no way of knowing that the information is actually deleted except trusting them.
Companies often face legal requirements that your data is truly gone, e.g. see the European Union's Data Protection Directive. So it's not just a pinky swear -- there is some legal force behind it. (Which happens to be true for the neighbor situation as well, so you really don't need to get pinky swears from everyone.)
> Companies often face legal requirements that your data is truly gone, e.g. see the European Union's Data Protection Directive.
Maybe that's part of the difference. In the US you have to keep records of stuff. At my company, we have to keep records for ~7 years, IIRC.
2) Google is like a storage locker where the managers rifle through the contents and tell you what crap you might want to buy based on what you keep in your locker.
You still have to trust the managers, since they're the only party with another key. If you don't trust them, you're free to take any legal steps to anonymize yourself when accessing the storage locker.
The problem seems to be that any additional layer of privacy or anonymity is only available to those who opt into it or go out of their way to implement it.