Are you unaware of the existence of loan sharks?

I'm aware of some who are currently in prison, and others who have left the business (which has got a lot more competitive as legal payday lenders have got a lot more efficient). Like burglary or any number of other crimes, we'll probably never be able to eliminate it entirely but it seems to be in massive decline and a pretty poor way to make a living - and one would expect it to be even less common in a world with basic income.