Per James Wilkinson Sword:
I was just watching an American film and thought, "Why don't kids steal everyone's mail?"

Theft from mailboxes happens but, here in the suburbs of Philadelphia,
it's rare.

When I visited relatives in the UK about 10 years ago, I was surprised
at the high level of perceived residential theft risk: bars on windows,
my cousin's husband felt the need to chain his bike even when it was
inside of their locked garage, and so-on-and-so-forth.

Ditto Germany.
--
Pete Cresswell