So far, all people who claim their "nephew" or "friend" owns their accused alt account, are from "poor" countries. It makes sense: a "signature income" makes a much larger share of your total income if your "local" income is much lower.
In general with common observation yes your have observed it correctly but in my experience all it was not necessary if a user has a certain goal and be honest in their activities. In my experience it's not about living in a poor or economically down countries. It's about users to have lack of experience and proper goal with a good mindset, these people also don't want to study, learn, understand a knowledge and apply everything to improve their personal skills.
Most of the users in the forum want to make quick money, they want it today, even without achieving the first rank. If they would observe the influential members (who are making 10 to 100 times more money only from signature and avatar campaigns than those of general members) and followed their footsteps then they would make better amount of money than they make having a dozen of alternative accounts and abusing different opportunities.