I agree it is not unreasonable, but I'd also note that bars have their livelihood at stake. While a child has their phone at stake, you cannot threaten their livelihood without a trip to prison.

There are no material stakes to the child other than losing their entertainment device. Might as well break the rules.

Limited restrictions for specific times and places is totally reasonable, I read the parent comment in a larger scope as it was about stopping addiction.

This and taxes, it's much much harder to get cigarettes as a teenager now because of the price