when you go to a restaurant, aren't you implicitly trusting most of their staff? if i couldn't trust some company to take care of my phone for an hour, i certainly wouldn't trust them to serve me food.
I'm not sure where you're from, but in the united states, employers can pay an hourly rate of $2-ish to people who are expected to collect tips. The stereotypical fast food kid actually has a better hourly rate.
Since when is the definition of a restaurant worker someone who does not make much money? Especially those not working fast food?
Naturally this only applies to the waiting staff, but then again, the chefs aren't going to be the ones handling your phone.