Yes, you are right, AnomalousMonk, for populating the inner hashes, I just blindly copied the OP's code, but AFAICS, quotes are not needed on either side of "fat commas" in the above hash definition, so that the relevant code could be changed to:

push @people, {
               id => $id,
               first => $first,
               last => $last,
               age => $age,
              };
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They are not needed on the left side of "fat commas" (=>) because the fat comma automatically stringifies its left argument, and also not needed on the right side of the fat commas here because the values are already stored into variables. And, BTW, with respect to boftx's suggested explanation, preserving leading zeros doesn't seem to be a sufficient reason, as it appears that any leading zero(s) in these variable will be preserved and that Perl will not "numify" the hash values, as shown in this example under the Perl debugger:

  DB<13>   $s = "003";

  DB<14> %h = (string => $s);

  DB<15> x %h
0  'string'
1  003
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