Number 1 is just weird

Actually, it does have some utility - and I've worked some places where it's the required style. Compare:

use strict;
use warnings;
use CGI; 

# oops typo, but I don't get an error until runtime
sub foo { CGO->new };

# oops another typo, but this  time I get a compile time error
sub bar { CGO::->new };
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Handy for catching typos and missing use statements.