Yeah hehe, I have received quite few of those scams from Nigerians [well they claimed to be Nigerian at any rate], a few from people I took to be white from America [could be wrong though] and some from Europe.
I've also had to fight off a knife weilding West Indian mugger when I was in London on my way back from work while I was in college and in my earlier days [late twenties] I jumped in to help an African American navy sailor fight off a bunch of italian looking guys who, well I don't know what was going on but he turned on me lol, maybe it was in the heat of the moment and didn't realise, and I never saw him again to ask.
I've also been the victim of an attempted pick pocketing while walking along Oxford Street, London, by a young white woman who was around the same age or so as me but she was caught by street cameras, luckily for me.
But yes, those Nigerians who do this [if indeed they are Nigerians, okay lets say they are for arguments sake] should be ashamed of themselves, lying to, and in some cases, begging others under false pretense.
Peace...