Yeah, the look that Phalanx pauses to give Robin is absolutely one of confusion. So, if there had been any question on the shopkeeper's part about the necessity of the warning, there won't be at that point. Phalanx has to take a second look at the skirt and do some thinking before they try reaching for it again.

And, blessedly, they take the instructions to heart. Though, if any buckles or ties need to be undone first, someone is going to need to help, because they don't bother with anything before stepping into it.