Thanks for your concerns re. medical privacy, Tothil, but it's not an issue. The phones used are hospital property, issued to each nurse for their shift. they are locked down for the use they are being given. The info is kept within the hospital system only. It works well. We're not talking about your friend Nurse Jim using his personal phone and then having his way with private records or information when he goes home.
My point is that photos on phones are everywhere. We use them for many reasons -- keeping track of where you parked, the exact name of the pool chemicals you need to pick up, the phone number on a flier in the grocery store, notes from a meeting on a whiteboard -- or the name and information of a bolt of fabric you're contemplating buying.
The smart shop owner will use this fact to his or her advantage rather than putting up signs telling people they can't take photos or worse, insulting potential customers.