There are all kind of perfectly good reasons why a member might prefer to post on some occasion as a GUEST with a different name.

On the other hand I can think of no good reasons why anyone would choose to post as GUEST with no name (leaving aside when it happens by accident or inadvertance). And I note that none of the nameless GUESTs on this thread (or is there only one?) have chosen to suggest one.

"...if there were no guest log-ins" - this isn't ever about guest log-ins as such, it's about guest log-ins without any kind of name, however temporary. I know I keep on repeating this distinction - but it's one that keeps on getting blurred, because it is quicker to say "GUEST" than "nameless GUEST."