Not being asked!
I was in a festival singaround at Bridgnorth years ago and after going round the room and passing over me they decided not to ask the idiot in red but eventually asked the girlfriend next to me if I sang. She was somewhat non-plussed and pointed out that the person to ask was the shy retiring poser in red. It wasn't the first time they had performed that wheeze, the year before if I remember. They thought they were doing a good job!
You couldn't say they hadn't noticed me, but then Bridgnorth became Shrewsbury and IMNSHO it has lost even that level of friendliness.