Seems undesirable if it doesn't automatically silence the phone by disabling incoming calls. If they still ring while in a sealed back, then I don't see the "artists" they're marketing yondor to, being very happy.
If I'm someone who works in actual life and death related matters and on a regular on-call schedule, I need to be able to
1) Still continue to have a life
2) Not have my phone completely disabled just because I went to see a comedy gig.
Having to leave the comedy gig when my phone starts vibrating in the bag is a good compromise, as is wearing a smart watch that can notify me exactly what the call or message is about before I do.
The selling point is to reduce visual / audible recordings of the performance, allowing artists to say or do things that may be problematic when taken out of context.
