It's up to a company to set its own policies around privacy and ensure employees follow them.

The fact that an employee worked somewhere with different, or opposed, privacy policies, doesn't mean they're unable to follow yours, any more than the fact that working at a company that used a 4-space-width tab to indent code means they're unable to follow your guideline of two-space indents.

What does it matter if an employee would be fine doing what you consider to be privacy invasive things at another company? If they can do the job you expect them to, following your company's privacy policies, then that's all that matters. Otherwise, their personal moral compass is absolutely none of your business, and it's offensively paternalistic to suggest otherwise.