Some of the more experienced ones can keep it going for months before any request for money, etc is made or the marriage proposals ever come to the conversation. All you know about this man is what he chooses to tell you. That's all you know.
When I broke up with my ex, I was talking on the internet to a woman in the Phillapines and it didn't take her very long to ask me for money. We were talking for a few weeks. I was the cats ass until I said NO. She claimed she was so poor up to that minute. I am sure she has moved on to some other guys who are lonely and desperate and naive.
Nowadays, I won't even waste my time talking to any woman who is not in my area.
OP how do you know "Morocco Joe" is even telling the truth why he cannot visit you ? I know the visa requirements are strict. For all you know, maybe he has a criminal record. As another poster mentioned, you only know what he tells you.