Oh sorry what I meant is actually:

Anyway the reason I said the latter syntax makes more sense is because I saw the latter syntax more often. For example In https://metacpan.org/pod/HTML::Template#TMPL_LOOP:

$template->param(
    EMPLOYEE_INFO => [{name => 'Sam', job => 'programmer'}, {name => '
+Steve', job => 'soda jerk'}]
);
print $template->output();
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This code uses reference(array) because of clarity and I think most subroutines uses this syntax.
However this line

has 'friends' => ( is => 'rw', isa => 'Array', default => () );
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is same as:

has 'friends',is => 'rw', isa => 'Array', default => ();
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which is not clear and as for me that looks just weird.
But when using reference, you don't have to use awkward arrow between 'friends' and 'is'

Of course, not using reference parameter saves some typing but that saves typing of Moose's author, not of us. And using reference is also not a big deal.Clarity is more important

These are all exactly equivalent:

has   'friends' => ( is => 'rw',   isa => 'Array',   default => () );
has    friends  => ((is => 'rw'), (isa => 'Array'), (default => ()));
has    friends  =>   is => 'rw',   isa => 'Array',   default => ();
has    friends  =>   is =>  rw =>  isa =>  Array =>  default => ();
has   "friends",    "is",  "rw",  "isa",  "Array",  "default",  ();
has qw/friends       is     rw     isa     Array     default/,  ();
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Moose has just chosen to write things the way they do, but you're free to choose any of the above, whichever is clearest to you - that's a lot of freedom! It's just a matter of taste, and arguing about it is just like arguing about whether your sandwich tastes better depending on if it's sliced diagonally, horizontally or vertically ;-)

Which is, by the way, exactly equivalent to

has qw< friends       is     rw     isa     Array     default >;
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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ