My cents, untested, before I crash.

sub file_sizes {
  my $match = shift;
  my %sizes;
  for (@_) {
    for (glob("$_/$match")) {
      $sizes{$_} = -s $_
    }
  }
  %sizes
}

my %txts = file_sizes("*.txt", qw,/home/*/docs
                      /usr/share/doc/txt,);
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