Even without a bribe, you still have to trust the minimum wage worker at the store. Motivated criminals or organized gangs could send people to apply to jobs at mobile providers. Come to think of it, that's probably already happening... spies too...

There's a big gap between the high trust and low salary that companies give their frontline employees. And despite (or because of) that gap, they're not motivated to do extensive background checks.

But the average employee at the Verizon kiosk in the local mall is arguably handling more sensitive data than an employee at the passport office in the State Department.