I think this is more an example of what we call “bullshit.” There’s a lot of it.
In America we particularly have a lot of "bullshit we think protects us from lawsuits even if it really doesn't".
The concept of supermarket greeter blows my mind. As a customer this would be a reason to NOT go to that supermarket.
As a potential employee I would have to be starving before I took that job.
Supermarket greeters are really for theft-prevention. It's not for the customer's benefit.