Great to tell people to put away their phones and not record because that really is obnoxious, but to actually confiscate phones is fascistic and shouldn’t be tolerated IMO. I mean who does he think he is?
A showcase user for https://www.overyondr.com , probably getting the service at a reduced rate, free or maybe even for some reverse payment in exchange for the publicly.
Cost for yondr should be pretty much proportional to audience size (physical pouches), and Jack White might offer a very good cost/visibility ratio for them. (I don't know anything about his typical audience size, but it might lean towards the smaller end of the spectrum relative to his indisputable fame)
If you don't like that trade, don't make it! But don't deny those who wish to engage in that transaction the right to do so by forcing them to have a "cell phones are welcome" policy.
This is a rock concert. There is no coercion to attend whatsoever. You are absolutely, 100% free to decline this transaction.