When out in public and someone is speaking very loudly on their phone, I softly, politely and with a smile say to them 'Excuse me, but I am sure you aren't aware of your personal conversation being heard by all these strangers'. Usually, out of embarassment, they lower their voice. Some don't care and will never care, but many will move or soften the sound. When I am working, I just stand perfectly still and wait. Eventually the customer stops and repeats what they wanted cut. I say (again softly and with a smile) that it's ok, I can wait until they are done. It frosts me that people think so little of the folks they are either dealing with or that are around them. My kids say I am being rude and just don't 'get it'. I think I am getting a small victory when they either quiet down or get off their phone.