The difference is in the culture you learn. So of course if you grow up poor, you're more likely to be poor. For example, you would think payday loans are normal if that's how you grew up.

The problem with the "evidence" you're using is that it can be interpreted many ways. It's merely a correlation.

In circumstances closer to controlled experiments where I actually gave someone money, they usually wound up worse off in a couple months, not better, unless I made sure the money went towards fixing a real problem.