Earlier quoted context omitted.
I don't think your test is all that good. If I'm out with friends, I try to consciously avoid using my phone when we're together so that I'm present and so that they know I value their presence. Those 15 seconds at the urinal are often the best time to check notifications before getting back to phone-free socializing. Agree with your other points though.
Might just be me, but I don't think it's appropriate to pull a camera out at the urinal
I don't mean to say it's not a valid concern, I just think that it can be done in a way which makes it clear that one is not doing anything weird.