Earlier quoted context omitted.
"...having to wait in a line to submit or retrieve your phone, be sequestered to a penned in area to use your phone, and then to have to wait in line again to put your phone back into that "prison" system again..." The vast majority of the time consumed in that process is simply getting out from where you sit/stand and back, which is the same in the "unjailed" phone scenario. Unless, of course, you were just going to…
I'm thinking about how annoying this would be at any sort of venue or music event. Someone said prior the main reason they'd use their phone in that situation is to group up with others they came with or met there if they get split up. I can empathize with that 150% and feel that, as someone who will never do more than snap a quick photo of a musical act for nostalgic purposes, the system in place to leave your phone…
A lot of the time your mates aren't looking at the phone at the right time, or there are so many people that you don't get good reception. Looking up and just finding people works pretty well.