An advantage of the "wasted variable" (I prefer to think it is an "intelligently used variable") is that you can perform a little validation:

my $object = bless {hi => 'hello'};

for my $suffix ('x', 'y') {
    my $method = $object->can("prefix_$suffix");
    $object->$method() if $method;
}


sub prefix_x {
    my ($self) = @_;
    
    print "$self->{hi} world\n";
}
[download]

Update: elaborate code to better show intent.