Not sure why, but find myself not reaching for them ever.

Simple, you're not a perl
a real perl
an idiomatic perl programmer yet :)

Or as Modern Perl would say experienced perl hacker, not sure if he meant level 4 or 5 on the Seven Levels of Perl Mastery scale

Why would I use below ...

Because you think in terms of map and grep :)

my %filter_map = do {
    my $ix = 'A';
    map { $ix++ => $_ }
    ( map { ($_) x 3 } 2 .. 6 ),
    ( 8 ) x 3,
    ( 9 ) x 4,
};
[download]

Like a fighter, you think in terms of kicking and punching, not bending and expanding your knees and elbows while rotating your hips :)