Micro-credit exists where a functional banking system for the poor is regulated out of existence...it is more a symptom of an over-regulated & poor economy than a solution to one.
Where do you get your information from? Some of the countries that have the highest success rates with micro-credits have pretty much no regulation whatsoever in banking.
Banks don't do what micro-credits do, period. If they would, they had a century to prove it and failed. Interestingly, after micro-credits were successful to the point of attracting the interest of the Nobel Price committee, several banks tried to move into this sector, smelling good business. They failed miserably.
If nothing else, that proves that you're dead wrong. Even where no regulations or economy stop them, banks a) didn't provide this service and b) when they tried it was a failure. In the same countries, micro-credits driven by non-profit interests were and are successful.