As others have indicated, Western Union use all sorts of businesses as their agents. (e.g. travel agencies, newsagents, convenience stores, post offices, etc). As long as the recipient has an agent located near to them, you'll have no problems sending money.
However, even Western Union (who make money from transferring funds) advise that you should never send money to a stranger using a money transfer service:
http://www.westernunion.co.uk/WUCOMWEB/staticM id.do?method=load&pagename=fraudIndex
Personally, I prefer to use Ikobo but some people seem to dislike it.
Chris