Leftover nametags

Every now and then while walking down the street, or on public transport or just out and about I see someone who has obviously been to some training session as they have left a sticky name tag on their clothing.

Is it just me, or are others always tempted to say "Hello Bruce" or "Hello Joanne" (as per their name tag), just to see how long it takes before they realise they don't know me and that they have just left their name tag on?