The only reason that my father-in-law has a job is that the national postal service in Parguay is nothing like the USPS.
We can rest assured that the bills we pay through the United States Postal Service will arrive almost without fail, but stuff disappears all the time in the Paraguayan mail. That's where 'Cobradores' or Bill Collectors like my father-in-law come in. He works for a couple of companies and drives all around the city to collect bill payments in cash or check.
The thing is, though, that there are no penalties for late payment so he often has to go back time and again to collect. Tough job.