I don’t understand the issue.
When “Mrs. Try” and I go out she brings her purse (sometimes a tiny one), containing her cell phone and usually some cash, keys, etc.
Why should a guy be insulted if his date (who doesn’t know him well) brings along her phone? If anything, it’s nice to have the insurance of a second phone (just in case his phone runs out of juice) and cash. I think it’s highly advisable that parents tell their daughters to bring a phone when going out.