spath - how do you know he's homeless? It's big business nowadays, pretending to be homeless - you can make a fortune begging, enough to buy loads of drugs.
spath - do you actually KNOW that OXFAM spent the money on prostitution as opposed to someone out there working for them spent some of his own money on it? Did the person put the prostitute down to expenses or say to them "here's some money in exchange for you dropping your knickers"? or did he feel the need and put his hand in his own pocket? You seem to be assuming the former with no actual knowledge.