I don't downvote. It is a cowardly habit.
There is nothing wrong with investing in a productive enterprise and expecting to share in the profits of that enterprise.
If a man is starving (or, worse, has convinced himself he needs a new iThing when he does not) and you loan him money you are either violating charity or enabling debt-peonage, respectively.
This is setting aside the exponential nature of compound interest, which is why debt-based economies always go bust, and focusing on the individual morality of the transaction.