Not to sound like too much of an egotist but some of us really are noticed an awful lot and spotlight effect sounds pretty alien to me. I am very tall (over two meters) so that is definitely part of it. I am very outgoing and I tend to go to events alone (because few friends share all my interests and I am fairly antisocial and impatient). All that congeals into many people remembering me and I don't remember them (except interesting stories separated from identities). I don't think most people remember me but many do, they have told me so. It would be quite an experience to just be able to be unnoticed in a crowd but it is one I have never really experienced in larger crowds as there is always some extrovert introduces themselves. I daresay intentional attention seekers and those with some physical quality that greatly distinguishes them from the norm would have a similar experience.